No matter what, be nice to wait staff. Smile. Make Eye contact. More often than not, the results are huge. Both for them, and for yourself. I'm very introverted but I make it a point to do this. Result: They are happier. I am happier. I get extra Steak on my salad. #JustSmile

This is all customer service roles. As someone who spent nearly a decade in retail I can tell you, dealing with the public sucks. Most people are 'Meh'. Many are horrible. I would bend over backwards for the nice customer.

A few nights ago I had a table come in that ordered off menu, I only mention because features are spoken, got their food, started eating, I stopped by to see how everything was, “oh delicious” as they gorge away, bill arrives, worst meal they’ve ever eaten.

Yeeaa, I know the type. Businesses do too good of a job at teaching people that if a customer throws a fit, they get rewarded with discounts or whatever. Imagine what the world would be like and society just shunned these types until they learned some manners :P