Yes, yes, educated people know that we all wear them, but that doesn't mean that we remember to peak around them. I was talking with someone here (the UK) about words that are different in American and British. He mentioned how funny it is that we call the devices in buildings 'elevators', when after all they go down as well as up. I responded, 'You do realize that you call them "lifts", don't you?'
He looked stunned for a second, and then said, 'Oh, we do, don't we?'
A similar item: what we consider 'breakfast food'. People have very strong ideas about this, different from culture to culture, and with little seeming basis in the character of 'good' and 'bad' breakfast foods. For instance, I've had people tell me they couldn't eat a hanmburger at breakfast -- 'too heavy' -- but will happily eat several slices of bacon and a sausage or two. They see or hear that the Irish eat plaice -- a mild whitefish -- at breakfast, and declare 'I could never have fish for breakfast' -- but hungrily devour smoked salmon, a much stronger fish, on their bagels.