thanks for all the replies.
Earl's wingshots are indeed something to behold. You can get a taste here:
http://www.youtube.com/watch?v=qJkpjqy7GcI
I agree that for 75/hr I'd rather pay for the lesson than pay for the exhibition, but for people who aren't serious shooters, they'd probably feel more like they got their money's worth out of an exhibition.
I'm surprised at mike's price, but it makes sense we got away with 800 bucks now that I think about it. The room owner is a religious man (the pool hall is actually in what used to be a church!) and so is Mike and I think they must have hit it off.
Jeanette's cost is pretty shocking

I knew she charged 10k for public speaking, so I guess it makes sense an exhibition is along the same lines. But damn, how does ANY pool hall afford that? I don't know a single pool hall owner with 10,000 bucks to spare even if he's successful and expects to get a few bucks back in beer sales, cover charge, etc.