One thing about a track "day" is tires. You can pretty much go through some pretty expensive rubber in a day. Our Caddy's had a new set of tires after one day.
That could cost more than renting time.
That is a good point. I know I didn't want to be riding worn tires when I took the motorcycle out on track days. The more heat cycles you've had on a tire, the less grippy it gets. And on a bike the physical consequences of those two little contact patches not gripping can be a little more extreme than sliding off track in a 4-wheel car...
That said, you might burn through a lot of tire drag racing too...
I would point out though that doing a track day or two on a set of tires doesn't "burn through them". You'll still have plenty of tread and they'll still be completely suitable for normal street driving. They just won't be nearly as grippy as they'd be new.
I think you're making assumptions on behalf of a population you don't really know about. We don't have to speculate, we have our very own Corvette-owning speed demon right here in our midst, we can conduct some research and find some real answers.
Ah well, there you have it, the research is right here for us to analyze. 
We're using the anecdote of a single dirt farmer in Iowa for this analysis? He just wants something shiny to go to/from the golf course and impress chicks

That said, if we're talking anecdotes... We have CD who has participated in a Cadillac track day experience. We have me who has participated in a Ferrari autocross experience and who has done multiple motorcycle track days. (And who has opined about how fun it would be to buy a "track car" but just can't justify the cost for something like that.) We have multiple posters who have talked about the fun of driving twisty roads.
I'd venture that those who seek out "road racing" type driving experiences are a slightly different breed than those who seek out "drag racing" type driving experiences. While I'm sure there's some overlap in that Venn diagram as the two are perhaps just different expressions of the "I wanna go FAST" gene, I think even in that overlap most would show a
very strong preference for one type of experience over the other...