I'm Isaak, the lead organizer of Future Forum. Specifically addressing the points regarding Future Forum:

By "ask for money (often retroactively)", I am referring to the grant made to the Future Forum (a conference held Aug 4 - 7, 2022). 

I don't know whether retroactive funding happens in other cases. However, all grants made to Future Forum were committed before the event.  The event and the organization received three grants in total:

Applications for the grants were usually sent 1-3 weeks before approval. While we had conversations with funders throughout, all applications went through official routes and application forms. 

I received the specific grant application approval emails on: 

• Feb 28th, 2022, 9:36 AM PT, 
• July 5th, 2022, 5:04 PM PT, 
• July 18th, 2022, 11:28 AM PT. 

The event ran from August 4-7th. I.e., we never had a grant committed "retroactively".

Cleaning up their mess included getting a new venue last minute (which was very expensive), which took them into large debt, and then, reportedly, being bailed out by Open Philanthropy (retroactively).

Knowing that the event was experimental and that the core team didn't have much operations experience, we had a budget for "logistical issues/fires" beforehand. This budget covered all of the additional expenses, including CEA's expenses. We never went into debt or were bailed out by additional grants.

That being said, and beyond the scope of the original post's concerns: Indeed, we didn't plan thoughtfully for the neighbors. They were already sensitized because the venue had multiple parties over the weekends before. Thinking that Future Forum was some new party and not knowing it was a relatively quiet conference, they called the police. We were forced to leave the first venue and swap into a new venue by day 3. 

CEA stepped in on day 1 and without them, the event would've been over on day 2, and day 3 and day 4 of the event wouldn't have happened — for which we're incredibly grateful.

I claim responsibility for not having foreseen and planned for this issue, and I also claim the default responsibility for all other operational issues and mistakes.

The points regarding the funding of Future Forum being retroactive are not true. All of this doesn't reflect on OP's grantmaking  strategies and the other points addressed in the post.

I'm sorry this has been roadblocking you - if it's helpful, you can email your application to the team: hello@futureforum.foundation

Thank you, Austin!

A non-comprehensive list of events, to my knowledge: EAG SF, MLAB, many socials open to EAs (announced e.g. the Bay Area EA Facebook), apply-only or invite-only retreats, like GCP's X-Risk summits. 
(I wouldn't be surprised if there were 2x more events than listed here.)

I hope this is helpful.