Lexical Morphology Joke!!!

Last semester I taught intro to morphology, and one of the things we do in that class is go over the basics of Lexical Morphology. And in the course of that we talk about fun stuff like bookstore vs. *books-store, mice-infested vs. *rats-infested, and so on. So I was sitting around with a bunch of non-linguists, and we started talking about how every place has a place that they make fun of. e.g. the US in general has Polack jokes, although where my cousin Kate grew up in northern Wisconsin they were all Belgian jokes (really). And of course Canada has its Newfie jokes. One person said that when they lived in Pittsburgh, everything was West Virginia jokes. And he proceeded to tell us the following West Virginia joke (apologies to anyone from W VA; this is mention, not use): Q: How do you know that the toothbrush was invented in West Virginia? A: Because otherwise it would be called a teethbrush. !!! I just sat there with my head exploding for a while, and then offered to give them a half-hour lecture on the topic, which to my shock, they turned down.