(A customer comes in and orders two large pizzas and tries to pay with a $100 bill.)

Me: “I’m sorry, but we can’t provide more than $20 in change.”

Customer: “What? Why not?”

Me: “It’s our policy.”

Customer: “Then you should have a sign up telling people that!”

Me: “Well, sir, if you look to your right you’ll see just such a sign.”

Customer: “You should have a sign that tells people before they get here!”