More on the economic difference between food and art from Carolynn Carteno (can't figure out tildas in Typepad, sorry), although she appears to have taken it down.
"I know nothing about art and my opinions
should count for nothing. The difference is that when I don’t like an
exhibit at an art museum, I don’t demand my money back. Or a free
pizza. Besides, this exhibit was worth the price of admission, even
though it is very sad."
True. I'd wager it HAS happened, although not nearly as often as restaurants.