I’ll add a corollary to it: sometimes you have to be the planner. Lots of people are like “yeah, I want to do $ACTIVITY but there’s nobody to it with.” There’s also a ton of people that are like “there’s nothing fun to do this weekend.” Post an event on Meetup / Facebook / etc. Say you’re going to do $ACTIVITY at $DATETIME and chances are pretty good you’ll find someone else interested in doing the thing with you. Good starter choices for $ACTIVITY include pub trivia, karaoke, and comedy nights but could also be things like going for a hike or a nice walk around a pond. It doesn’t have to be at a bar or expensive.

If you do this often enough, you’ll develop a group of regulars who will also want to do fun things and you can get one of them to host.

Be the first mover.