This problem isn't limited to conferences. I'm a woman and an engineer, and I can't count the number of times I've met someone at a casual tech meetup and the first thing out of their mouths was "You must be in PR." If you want to make a small difference in making the world a nicer place, just ask me what I do.
Booth babes and female sales reps are an interesting thing to discuss, but we can't individually change the whole marketing culture. But we can individually make the tech scene more inclusive just by being more sensitive about the way we interact with other people. So please, please, please don't make assumptions about me or start presumptuously explaining things to me without asking what I do.
Why is it such a problem, though? It is statistically unlikely that a woman is developer, so people react accordingly. Does it really hurt so much to say "no, I'm a developer"?
Yes, it makes the very demographic people are trying to reach out to the most feel very unwelcomed. It also means that many people never challenge their assumptions and the lady doesn't get to correct them.
Booth babes and female sales reps are an interesting thing to discuss, but we can't individually change the whole marketing culture. But we can individually make the tech scene more inclusive just by being more sensitive about the way we interact with other people. So please, please, please don't make assumptions about me or start presumptuously explaining things to me without asking what I do.