I get you, though. A mailman once made a completely inappropriate joke about my last name that I already had heard so many times and I was just dumbstruck. He was so excited and gaudy to let me in on it. I'm sure he thought I wouldn't know that one. Hopefully he could see the life leave my body, when I monotonously answered "never heard that one before" and remembers that the next time he thinks of a joke about the name of a customer.