I'm still pretty new at the modeling game. I started basically from scratch in late April of this year, and so far I've easily invested over $1000 in models, paints and supplies, spraybooths, and airbrushes. There are now few paint colors I don't have, so now I only have to replace them. I'm pretty well stocked up on tools (I don't do a lot of PE, so no special tools for that. Yet.), have a bunch of kits to build in the stash so I probably won't be spending any more money this year. Well, maybe the odd jar of paint!
I expect to spend maybe $500-600 per year on new kits and replacement supplies. If I spend an average of 1 hour per day (365 hrs per year) at $600 that is only $1.64/hr. That's little more than 7 hours per week, which is probably too little. I figure it's closer to 10 hours per week, or $1.15/hr. That's cheap! Even if I doubled the budget, it's only $2.30/hr.
The average green fee around here is $65. Figure 5 hours to play the round, that's $13/hr, and doesn't include any beer, hot dogs, lunch, dinner, or payoffs on bets that usually happen.
As qmiester's wife says "At least I know where he is and the money isn't being spent on booze and broads".