So your proposal is to start an ad hoc friend group with people who come up to me, and try to become friends with them personally?
I'm not sure I'm the right person for that. I live in a suburb, not the city that I do the surveys in. And I'm extraordinarily boring, and too old.
It seems that I should try to think bigger. Try to find a way to help these people connect with each other. Something in person, not an app like Hinge. Maybe, hold a sign that says ad hoc meet and greet at such and such time and place, after collecting a list of common interests and putting those interests on the same sign that says the time and date. That could work.
In my city, an older guy organized an “urban hiking group” where he would plan walking routes through the city, usually stopping at a restaurant for brunch. It was very popular, but probably a lot of work. He was semi-retired, so he had the time to do it. He did research to have talking points on the history of some spots we passed, like a tour guide.
It was a great low key meet up. You didn’t have to make friends with the organizer. If you were walking with someone you didn’t really like in the group, it was easy to drift to talk to someone else.