Very few bulk petroleum dealers received much of anything after the mid 60s and early 70s.
HOWEVER, the wholesale dealers I am familiar with would receive two grades of gasoline, diesel, kerosene as well as boxcars with TBA (tires, batteries and accessories) from a larger facility. I know of some places in my part of the world where a boxcar with TBA would be spotted (typically for ease of switching, on the local team, not the fuel dealer's lead) and the dealer would pull out his tires and batteries and fan belts and radiator hoses...sometimes small barrels (about 30 gallon vs 55 gallon) with 90w transmission or gear oil and 5 gallon cans of grease (although my dad bought in 30 gallon "cans".
Then after the local dealer got his product loaded to his truck, the next local would pick up the outbound car to another dealer down the line.
Nearly all bulk fuel dealers in this part of the world had warehouses to store all the miscellaneous merchandise and product. Some (most) old wooden structures with loading docks; others had old brick warehouses. Some of the older wooden structures were covered in corrugated "tin" or sheet metal. Locally most was of the used "tin" was "retasked" when the temporary structures (Quonset huts) were dismantled after WWII. As often as not, these warehouse buildings were adjacent to the above ground fuel storage tanks.
I grew up in the 50s-60s in a town that had adjoining Conoco and Cities Service refineries. (on opposite sides of the main line with a fair number of tracks for each for loading/pick up and so the local switcher did not foul the main lines.) I recall the irony that the Conoco or the Cities Service jobber could just drive his 6 wheel tank truck to the refinery and pick up his own fuel, but the Sinclair and Phillips jobbers had to have "generic tank truck transports" (Groendyke was one large tank transport company.) Even though all the fuels came from the same refinery...they did at least add the "secret ingredients" so whoever had "no knocks" additives would still have it. Interestingly, Gibble and Deep Rock (both had refineries in Cushing, just 70 miles from my town) would have trucks from their refinery deliver. Texaco would occasionally deliver a tank car to their bulk jobber adjacent to the local 14 track yard.
Now think about this: Prototype railroads would not switch every industry every day. Few industries require or generate that much in bound and out bound traffic. So, unless you are modeling KC or Chicago or New York or any of the major industrialized cities, small farm towns and small to medium cities (10,000-50,000 people) would far more likely have around 8-12 industries with one or two having daily set out and pick up...while usually one or two other customers would have a set out or need cars moved so the empty is no longer blocking the door and the loaded car can now be unloaded (or vice versa).
Let me take you thru my current layout plan and the "evil day dream" layout that I am considering...
Current Layout: ATSF switching district in Oklahoma City. (really existed, and "some" of the industry types were real customers, although I changed all the names, I also played with the union contract so that the crews assigned to the "Stockyard District" were not allowed on the main line. Thus it operates much like a short line...it "interchanges" cars to the main yard via the "south switch job" while the Stockyards crew stays dedicated to moving all the in and out bound traffic with the speed required for iced cars and livestock cars...other customers are just along for the ride.)
Because of space, I am planning for about 12-20 in and out bound cars daily. Traffic will ebb and flow based on a random matrix.
I have a total of 3 stock car unloading chutes, so stock cars get pulled and spotted twice a day, sometimes three times daily during rush seasons. But in the early 60s, there might be days with just one livestock car moves, livestock movements are slowing via rail.
I have seven loading docks at the two livestock packing houses. Again, in the 60s, refrigerated trucks are replacing a lot of meat via rail, so the larger plant moves 2 or 3 cars daily with an occasional second set out for the overnight crew and the other plant moves even more by truck...maybe 1 or 2 cars each day.
The flour mill gets a few boxcars of grain every day or two and ships a fair amount of covered hoppers for commercial customers and bags and boxes in boxcars for grocery distributors to retail markets.
"Onesy-twosey" customers would include a bottling plant, a machine shop/foundry/custom workshop, lumber yard, bulk fuel dealer with warehouse, a couple of team tracks, a hardware and paint warehouse, a commercial fruit and produce wholesaler (restaurants and schools), furniture store, flooring/carpeting/tile dealer, a small women's ready to wear manufacturer, a steel and iron fabrication shop.
There is a small chemical processing facility that receives inbound chemicals and produces a product used at most of the regional refineries. So tank cars in as well as an occasional boxcar for barrels are received and outbound cars are boxcars loaded with 55 gallon drums.
And the other customer that receives and ships multiple cars per week is a wholesale grocery and produce warehouse. (Think wholesale location for Safeway or Piggy Wiggly.)
My 15 x 19 layout is an around the wall shelf with a 12 x 4 wide peninsula. I have 23 industries or customers. Several have multiple loading spots or docks or chutes and some have multiple buildings or warehouses. I have 38 car spots on the layout. By that, I mean that I have one dock, that is a car spot. If you can spot 3 cars on a team track but there is only one dock, that is still 3 car spots. Although the flour mill has room for around 10 cars, there are only 3 loading/unloading spots. There is a chute for grain loading and a car dump at the same location, so only one car can load or unload at the elevator, but the mill itself has two docks for pallets of 100 pound bags for commercial or wholesale customers or cases of retail 5 and 10 pound bags of flour. And so on...
The exception is the Frisco interchange and the "interchange" track where cars are delivered and picked up from the Santa Fe "South Switch crew" that makes multiple trips each day from the "36th Street Yard" in northeast Okla City and runs south to Moore or Norman OK depending on other traffic and how many cars they need to work.
What part of the world? What year or era? Urban or rural or mixed? The size of your layout? Do you operate or just "run laps and occasionally set out a car"?
All of those questions will cause some adjustment in how you switch your layout and how you operate it.
On my layout, priority is given to inbound empty iced reefers going to the two packing plants, inbound livestock cars headed to the stockyards, inbound loaded reefers with perishable fruit, produce or meat products. Outbound priority is the loaded iced reefers from the packing plants. Obviously, if something is marked "expedite" then it will be moved in the first available movement.
When I buy a new piece of rolling stock, I don't just buy something I do not have already nor do I buy simply because I like the paint scheme. I consider if any of my industries/customers would have any business to RECEIVE shipments from someplace that railroad services. Outbound cars are typically "home road" meaning Santa Fe.
For example, I have livestock cars from most all the railroads in Oklahoma. I certainly have ATSF stock cars and MKT, CRIP (Rock Island) as well as Missouri Pacific and Texas Pacific. I also have SLSF (Frisco) stock cars along with some foreign freight cars that are not contiguous to Oklahoma City such as CB&Q and UP. Finally I have some lease/private road name stock cars: Armour Stock Express and Swift Stock Express. I have a total of 26 stock cars but will probably reduce some of those as surplus. All those cars have unique reporting marks.
Space considerations: The stockyards and the packing plants occupy a space about 12ft long and maybe 2 feet wide on the peninsula. How did I do that? Well, the packing plants are one building, approximately 42 inches long by 4 stories tall and 6 inches wide. (custom built by Model Structures owner and OGR forum member Joe Fauty) This structure is built using OGR Ameritowne components. The narrow view of the building is "hidden" with another structure serving as the "slaughter house".
Since the structure is on a peninsula, you can only see the one side at a time. By using different window treatment, different number of loading docks and use of different paint, the two sides look like different structures. The stockyards are at the end of the track on that side of the structure. On the "west side" of the peninsula, there is room for 7 cars at docks or livestock loading chutes. And for ease of operation, there is a runaround track that keeps access to the stockyards open even if cars are spotted at the packing plant. There is also a "cleanout" track that can be used to hold a car or 2 for a few minutes while switching.
That steel fabrication industry is simply an HO AHM container crane from the mid 90s straddling the single track spur in a corner with a false front structure of a "metal prefab" with one track that can go inside the building. I have room for a flat or gondola under the "overhead crane" and a car inside the structure. I think I could crowd that a little and have room between the switch that serves the industry and the overhead crane for a flat or gondola. While I doubt I would ever want 3 cars at that industry at any given time, having another car spot for holding a car (off spot) would give me more options.
The question is not "what industry to model" but should be "what do you want to model?" The sky is the limit. YOU need to go out and discover what industries you want that are reasonable to help you put your railroad in a specific time and a specific region of the country and more importantly, cars that would be used at the industries, in the era that you want people to accept when they visit your layout.
When I was deciding whether to stay in HO or to move into 3 rail, I knew that 3 rail would require a lot more real estate and that would keep me from modeling a 30-45 mile section of railroad. So I started looking at branch lines and short lines and realized that "creating my own railroad" would require lots of decals and custom painting...or I could find something that would give me the same feel. I am impatient, one day I took to the "surface streets" rather than the clogged Interstate and crossed a couple of tracks...the next time I tried a slightly different route and stumbled across a neat looking elevator and mill (dog food...go figure) and that was when I started exploring what I discovered to be the east end of the Santa Fe Stockyards Switching Zone in Oklahoma City.
I was told that at its height, there were no less than 5 switch engines assigned since all traffic began or terminated in the 36th Street Yard some 10-12 miles away from "Packing Town". I considered the prototype but realized I did not have enough room and the "yard" would be a single hidden stage track. That really cut deep into 5 working switch crews. Plus, that was steam era, I decided I wanted to do the transition from the Santa Fe "Zebra" to "Blue/Yellow" which was 1963ish.
So, I came up with a design and a bogus scheme on how my version was the "real" version of the railroad. And other than a Santa Fe employee or a Santa Fe rail fan, or a history buff, who is to argue?
After all, it could have been....right? (It works a little better if you don't over think it and kind of squint when you look at it. Works for me.)
