I have other hobbies, I just like my trains the best. I have a rather huge collection of diecast cars and trucks. In fact, diecast collecting lead me to trains. I received a Christmas catalog from Matchbox, and it included an HO set that I thought would look good under my Christmas tree. That jump started the whole danged thing. I don't buy much diecast anymore, only models that will fit on my layout, or certain models that just really jump out at me. However, I still like to move around my displays, and I'm getting ready to build a new display case for more cars.
I'm also really into old horror and sci-fi movies, collecting DVD's and even the occasional action figures and movie posters. A large horror convention is held twice a year in my hometown, so I make it over there at least once a year.
Then there are my Jeeps. I've had my 1981 Scrambler for over 30 years now. It is in rough shape these days, but it is mechanically sound and can run through the trails with the best of them. I also have a 2005 Rubicon that I've been driving for the last 10 years, and I'm currently investing in a lot of upgrades as I prepare to pass it on to my son.
To address the original question, my old hobbies were basically drinking and smoking. I found that those ran contrary to my desire to remain married, so I decided to leave them behind. Toys and trains were my way of filling the time, which is probably why my wife never complains about my current hobbies.