Specific and punctual activities? Getting together to chat with like-minded individuals does require showing up at the right time, yes. But like, how else will you meet people? You have to agree to show up at a time.
The topics I discuss at meetups I attend - software development, business development, and just geeky folks who like to discuss what they're hacking on - don't particularly have punctuality needs.
You have to organize it by some location metric. It would be cool to have more options - let the Meetup folks know what you'd like!
