Insightful post. I've noticed the same thing by going to Reddit meetups. With the exception of recurring events (like boardgame night) you really only see the "regulars" once a month, so if you miss one meetup, you really lose out on a chance to get to know anyone. That, and despite bars having the right atmosphere for a meetup, it's usually impossible to talk to anyone outside of the 3-4 people directly next to you.