Advice may not be what you are seeking, but a few things jumped out to me:
Pouring thousands of dollars into a casual meetup, even over the years, tells me of it being less casual than what is described in the OP.
I have never had more success trying to cater to different diets, budgets, asking for opinions on restaurants. Organizing a club needs, at least at first, a near totalitarian approach. _You_ pick a nice place, hopefully decently affordable, assume e.g. that everyone will drink and if not the club soda or coke will have to do.
Eventually, the group self-optimizes for the sweet spot in things such as age gap between its members. The ones who don't like the types of places you pick, the tone of the meeting, demography, etc. will drop over time.
A $10 pizza from Costco a hundred times is a thousand dollars. Coworking space fees for a couple of years is a sum of money. Meetup organizer fees add up.
I have never had more success trying to cater to different diets, budgets, asking for opinions on restaurants. Organizing a club needs, at least at first, a near totalitarian approach. _You_ pick a nice place, hopefully decently affordable, assume e.g. that everyone will drink and if not the club soda or coke will have to do.
Eventually, the group self-optimizes for the sweet spot in things such as age gap between its members. The ones who don't like the types of places you pick, the tone of the meeting, demography, etc. will drop over time.