Because your "family's parents" (aka: managerial class) have absolutely no compunctions about firing you at the drop of a hat, and thus evicting you from your "work family". I'm not saying to be rude - be nice obviously... But these people, you included, are working for money at a place that has money.
And I would much rather have the time and socialize at events and places that aren't related to a work function. In that case, me leaving a job for whatever reason doesn't automatically remove my "friends". (And no, I don't think many are actual friends at a workplace. Politics and decorum are definitely a thing.)
I don't live in the US, I won't be fired at the drop of a hat.
They managers and colleagues are also just people I spend a lot of time with. I know a lot about their private lives and they about mine. I could work at other companies doing similar things for similar income but I stay at this one because I believe in the things it's trying to achieve with its products (not very successfully yet, but I do what I can to improve things...), and so do my colleagues.
And yes, it all happens against a background of making money, but it's also a huge social thing. The two aren't opposites.
I actually did leave this job at one point, still got invited to the company barbecue, and when my new job didn't go so well (didn't click with the culture there) and a few other programmers had left the old job, I got asked back and did. There are several ex-colleagues I still have contact with.
I lead a boy scouts group, during summer camp last year we weren't allowed to go in public pools because of Covid, so I asked if we could use the pool at our founder's house because it was in the same area, and he thought that was a great idea so we did.
In the end it's people you spend a lot of time with, of course it's social.
