I think prior to the internet age, it was a lot more important to have regular meeting locations, dates and times so that potential members (and forgetful current members) know where they are going. Now that every club has a website (right? right?) it should be easy enough to publish next meeting locations.
When you have less than 30 members, with 20 regularly attending, someone's basement is fine. If things go well, you'd outgrow it. My club meets at a brewpub but we've come very close to outgrowing those accommodations several times last year.
How about a VFW hall or Firehouse? Someone has to have a family member who is a member of some kind of social club with a clubhouse. Even if you don't, I bet a firehouse would let you use their hall regularly if you leave a case behind.
Depending on what your real estate market is like, once you get to 80-100 members, it may even be time to start talking about leasing a clubhouse of your own. How cool would that be? Bar, movie screen, pool table, FTW.
Realistically, try finding a restaurant that is BYOB and pick a night when they are normally dead. Approach the manager with the idea and make sure everyone orders food.