I was on the board of directors for a local Linux Users Group and can echo the difficulties in finding a venue. In a city full of empty office spaces on a weekday night it was virtually impossible to find a stable meeting location. Without a stable meeting location you are much less likely to establish a core group since people do not like to have to learn how to get to different venues. Mozilla hosted us at one poin…
I was involved a tiny bit in reviving a local interest group of high-powered programmers. Another person, who did all the actual hard work, of meeting organizing, got meeting space at a Big Tech company...
Unfortunately, as a Big Tech (and in the surveillance capialism space), it was complete with signing in with security in the lobby, getting a guest badge for the visit, going to whatever presumable compartmentalized area, and the company presumably doing all the snooping things they could think of...
Every time I considered going to a meeting, the idea of going out of my way to be Big Tech's b-word, before I even got into the meeting, was a turn-off.
I like your community centers idea. The public libraries here have some meeting rooms. Sometimes someone at a university department can open up meeting space to the public.
Someone else mentioned makerspaces, which is an idea I hadn't thought of, but maybe complementary to makerspaces, as well as great marketing for adding members.