How can I have so much in common with a person, yet completely dislike them?
Computing events (so many stereotypically smelly antisocial people)
Fight sports (many wannabe criminals and general low lifes)
Ecological gardening (lots of self righteous hippies)
Then again, I guess if there are so many people I'm not fond of interacting with, maybe it's not them...
(to be fair there are also people in the above groups that are normal, but they're minorities)
Of course there are also people with social skills who attend those meetups, because e.g. they're just new in town, but if they meet some other people with social skills they will probably become friends with them, start organizing private meetups, and drop out of the public ones.
This seems to often be a problem with public board gaming groups -- they get filled with players with antisocial tendencies, who scare off any new players.
In bigger cities, though, there's a constant influx of new arrivals so it's not so bad.
It is not comfortable, but you will regret more not attending an event than if you did. It took one or two times of realizing that "I'm tired" at the end of the week was no excuse to avoid making friends.
You have to go out there and meet people, they don't necessarily have the will to meet you.
But eventually I realised I mostly regretted attending. Sure, you can meet people, but it's a setting that creates an initial bad impression and with people who are probably a bit socially awkward. Doing the initial greeting stuff got really old (job, home country, etc...) and most people were uncomfortable skipping it.
So now I never go to events to meet people. I only go if I would go anyway, because I'm curious enough or know I will enjoy myself. That's my recommendation, anyway.
Photography. I love the image making and the enjoyment of the subjects, but most of the photographers I've met through clubs / trips seem more motivated by having the latest kit. Which isn't me at all.
Group-led scuba diving.