I'm a bit confused by you using NIMBY and YIMBY interchangeably here, but most of the YIMBY activists I know come from people who got into housing policy becaus

I'm a bit confused by you using NIMBY and YIMBY interchangeably here, but most of the YIMBY activists I know come from people who got into housing policy because they couldn't afford to live in SF. They're all renters, and most come from a lefty political background. Fundraising events are pretty common in this kind of environment: if it was landlord driven, i'd imagine the tickets would be more in the thousands, as that's common for traditional for party political fundraisers in US cities, where you are paying for access. I'd compare it to, say, the Harvey Milk Club Gayla, whose prices you can see here: https://www.milkclub.org/gayla https://www.milkclub.org/gayla