I stopped giving tips after eating in this one Vietnamese Restaurant, we left a 10% tip because that was all the change we had in our pocket and this crazy waitress came running out of the restaurant shouting "What's wrong?, didn't you like the service? was there some wrong with the food? We were dumb-founded and we asked her "why?" she said "you only left this (6 dollar) tip."
That just pissed us off about tipping. It's called "gratuity" and for the last few years we stopped tipping (except when the service is exceptional) and it doesn't seem to make a difference.
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