Common Sense not so Common

A customer comes up to the counter with a popular diet book.

Customer: What's your return policy?
Me: 7 days on most things, excluding sale items and things can't be unsealed if they come sealed. Is it a gift?
Customer: No I just want to try it out and see if it works.
Me: Oh. Okay...
Customer: Well if I don't lose weight I should be able to return the book right?
Me: Ummm... Well, as long as the pages are all there and you can read then the book "works". Whether the diet does or not isn't really the book's fault. So no.