Actually, you'd be surprised; the "mathmo" stereotype is much stronger (and infinitely more true).
Having done the German equivalent of BMO, I'm actually not surprised at all. Still 1) most of those people are really nice despite being very geeky and maybe a bit unsociable and 2) I don't like being stereotyped .
There is a clear distinction between applied and pure mathmos, in that the former are much more sociable and have a lot more sex than the latter. Fact.