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.
We are all multifaceted people and we often don't acknowledge that. Even Richard Feynman played the bongoes.
Except: Church organizations. And it seems such organizations prefer that you are also Christian or are willing to fake it.
Furthermore, the poorer one is, the less likely one can take advantage of these things, especially in a town of around 50k or less.
I have lived the past 13 years in 3 tiny towns (under 100); just go to the bar every night. Made both good shallow and good deep friendships like that while I was over 30 most of that time. Mind you that was in another country with another language than my native. Personally I get depressed by big cities much faster; people I met when living in those are far (acting) busier and so need to keep things shallow.
Also, I seem to have some thing that people find weird; I can make and sustain deep friendships via internet chat alone. I have friends I speak to every day, who would do anything for me and I for them who I do not even know what their voice sounds like. I have started, ran and sold companies with friends who I have never seen or voice chatted to.
The digital equivalent of those places are Facebook groups. meetup.com, although their mobile redesign is a complete joke. Linked in groups. In the UK we have gumtree, probably Craigslist in the US. There's probably more, just sounds like you never looked.
You're looking for digital bulletin boards for your area, groups need new blood as much as you want to find them, you've just got to look.
Plus, of course, the local college night classes.
I just searched meetup for my costal corner of a home town of 20k in the UK and it had a bunch of meetups nearby, so it's pretty easy to find stuff.
Another observation -- finding new friends usually requires spending money for social activities. That's OK, but one has to be ready to spend more money than usually. I'm not saying that "free" activities never work. It just gives you fewer chances.