(I work at the hotel bar, and at the time was the only one on duty. Two days before I’d jammed my fingers in a door and as such couldn’t use my left hand properly, and was wearing a bandage so the guests would see. We also shake our drinks using a shaker and glass so the customers get a bit of a show.)

Customer: “I’d like a Sex on the Beach, please.”

Me: “I’m sorry sir, I can’t make any shaken drinks at the moment since I can’t use my left hand.”

Customer: “Oh. Well, can you make something else that’s shaken?”

Me: “Um, no. My hand is injured, and shaking one-handed isn’t a good idea.”

Customer: “You just don’t know how to make the drink, do you? Trying to get away with something simple?”

Me: *proceed to tell him the recipe of several shaken drinks* “…but I can’t do that because of my hand.”

Customer: “I bet you I could shake one-handed. You’re just inept.”

Me: “If you can do that, the drink’s on the house, but I won’t be responsible for any damages or spills.”

Customer: “I’ve got a free drink then.”

(He tries to shake it, and inevitably screws up, breaking the glass and spilling ingredients all over himself.)

Customer: “I want a refund!” *storms out*