I wouldn't of expected it to tend towards 30+ year old people especially in the Bay Area. Any overlap with other shall I say "cultural subgerenes" that you've noticed? Say PC Gamers or people really into sports?
I’d say that most of the people at these events are not in tech. As far as geeks vs jocks - I’d say it’s pretty much normal people. Or perhaps what’s normal for me. Perhaps slightly more hippy / burner than the average person.
I thought about it more. My definition of normal is very inclusive. There are socially awkward, social butterflies, more and less conventionally attractive, retired and middle aged, married / unmarried, all sorts of gender identity and sexual preferences at these events. There are events specifically geared towards LGBTQIA+ folks. Many events are hetero-normative and gender normative - I think that’s a function of where people feel safe and find community.