It is hard enough to get people to show up if it is free, requiring people to pay to attend a casual meetup would not work in our situation. Who is going to foot the multi thousand dollar per year bill for meeting space?
This is why municipalities need to provide this space for free. It is a very hard burden to get a single person to foot the bill for meeting space, whereas the municipality can charge everyone $50/year on their property taxes and build meeting spaces which everyone gets to use. People love to moan about taxes but I think this is one of those problems solved better in the collective.