At the risk of being politically incorrect and stereotyping, I thought I'd throw this question out there to see if anyone has an answer. It's a real problem and there are hard statistics to back it up.
http://www.npr.org/display_pages/fea...e_1329241.html
I'm sure the problem isn't as big at nice restaurants, but at places like Pizza Hut where the waitresses make $2 an hour and depend on tips...I hear complaints all the time. My wife has been a waitress and a delivery person and she says that 95% of the time, blacks don't tip at all.