Did you ever think that you might just be talking to idiots, rather than jumping straight to the sexism conclusion?
Errr.... you used the word sexism, I didn't. Call it what you like. Of course I was talking to an idiot, and, like I said, you get fed up after the 30th time of something similar. Just for the record, when he saw my expression, he followed it up with, "Well, most women can't fly. I mean, my wife doesn't fly". I think it's called digging a hole and then making it deeper.