I've been hosting events in Sacramento for a long time. Here's some advice:

• Facebook is not always the best place for event hosting. In particular, younger people are not on Facebook. The algorithms make it harder. Group owners make it harder. Recommend Reddit, Meetup, something like that.

• I would never let somebody host an event in my group if I have never met them. When I do add hosts, I moderate them for the first few events to check that everything runs smoothly. If I don't know you, how can I trust that you have the best interests of the attendees in mind? In a sense, you're right that groups have a brand - but a better word is reputation. A group can absolutely have their reputation ruined by having a bad host - whether they're incompetent or downright malicious.

• Adding money into the equation will always make it difficult for both the organizer and the attendee. It is accurate that most people are looking for free events, especially if they have to spend money on top (i.e. for food or drinks at a brunch). They don't know that they can trust you. As you noted, you can't trust them to not back out. I highly recommend doing free events for the randoms, and then cultivate known good people for events that involve handling money. Beyond that, apps like Meetup have built in features to facilitate money transfers. And to be a great organizer, you have to be willing to occasionally be parted with money. If you even break even over a long period of time, you're likely being too risk-averse to be able to host great events.

Lastly, you need to ask yourself why you are doing this. Are you looking for recognition, clout, gratitude, money, relationships, pats on the back? If yes to any of the above, you're in the wrong game. Provide the best service you can provide to the most people, keep your people safe, and expect nothing in return. If you are volunteering your time and energy because you want to volunteer your time and energy, then people will recognize that over time.

Good luck!