Luckily I work in a kitchen so I don't have to deal with people. Though last night apparently this table complained that their steak was overcooked (barely overcooked) and their pasta was cold (which it wasn't, I know since I was the one who made it and my boss, the chef, said it wasn't). Then they had the gall to curse at the chef/owner about him having the balls to server such food. Yeah, cursing at the owner isn't a bright idea. He kicked them out. lol.

My favourite are people who modify their food (not an allergy warning but a legit modify) to remove something that isn't actually in the dish. Oh you want that with no cheese? IT DOESN'T COME WITH CHEESE! Then again, in such cases the server should know better...