My local hobby shop closed last year, so my day-to-day purchases dropped to near zero. But since then, I've set my sights on some specific locomotives I've admired for a long time and I've been getting them one at a time. Just now I was counting, and much to my surprise, I seem to have bought $1400 worth of them last year.
None of that affects the household budget, since I put a bit of "leftover" money aside each week for hobby purchases, and when enough accumulates, I buy my locomotives with that. My current plan is for two more in the coming year.
But the recent locomotive purchases aren't the norm for me. Usually, it adds up to maybe a couple of hundred a year on cars and track.