[rmc]

Yes hackathons etc. are male dominated. No-one's saying they aren't.

The question is should they be this way, and if they should not be, what can we do to make things the way we want them to be like.

Things can be funny and sexist at the same time. Humour doesn't exclude any and all behaviour that someone wants it to. Sometimes the fact that it's funny is the sexist part, as in, the fact that 'humour' is used an excuse can be a symptom of sexism. It would be rare and mostly unacceptable for a bigwig businessman to do a black face show (à la an episode of Mad Men) and then claim "hey I was only being funny".

A thing might be funny for some people (e.g. straight male hackers), and be off-putting for others. If the others are the people who you think should be participating more (e.g. women hackers), then you might have found the reason why the world isn't the way we want it to be (i.e. this might be why hackathons are male dominated).