I don't know if you currently work in the restaurant/bar industry, or if it's something you have done in the past.  I have worked both and I'm always shocked at what a jerk people will make of themselves in public.

This story is just too good not to tell you about. This couple comes into restaurant tells the waitress they don't like her name and call her something else. Then she is accused of flirting with the woman's husband and doesn't receive a tip?  Wow, you thought you had crazy customers, this one takes the cake.