At some places, the wait staff makes A LOT of money through tips. Hooters is one I can think of right off hand. And the fancier restaurants where the final bill is in the $100's. Again, there is no obligation to tip, but it is an accepted custom here.

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"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."
- Albert Einstein (1879-1955)

"God is a comedian playing to an audience too afraid to laugh."
- Voltaire (1694-1778)

"I shall not waste my days in trying to prolong them."
- Ian L. Fleming (1908-1964)