Object: a shirt that says "Property of ..."

Boys and girls, have you ever seen a shirt like this one? (Show them the shirt and let them answer.) A lot of people wear them, don't they. You can buy them in the store. Maybe you have seen some there. When you wear them it makes other people think the shirt doesn't really belong to you. Of course, everybody knows that's a joke, because people buy these shirts to wear and that's what they say on them when we buy them.

Why do you suppose people like to wear shirts that say "Property …