I often wondered about this behavior. Every so often I would see someone go to their car in a parking lot, sit down in the driver's seat and just... go nowhere. Engine is running, music is on, driver has a 1000-yard stare. It's so far removed from my own experience - I never do this - that for the longest time, I couldn't wrap my head around it. Somehow, the phrase 'after a long day' made it click. So thanks, OP.

Apartment living also showed me that some people just hang out alone in the car instead of in the apartment. That I can understand as some units can be downright claustrophobic if you have a big family. Want privacy? Get a car payment I guess. :(

I've found myself sitting alone in my car in an abandoned parking lot just listening to some music and wondering what I'm doing with my life. The strange thing is that, by all objective measures, I have a really good life. I have an SO that I love more than anything in the world, and which is fantastic to me, I have parents and siblings that I have great relationships to, I have a job that I really enjoy, and I have good friends. Despite all that, I sometimes get this need to just "disappear" for a little while and isolate myself while listening to sad music. I don't really enjoy it either, it's more like some kind of cathartic feeling, like theres some kind of sadness in me that occasionally just wells up and needs to be given some space. It's quite rare (maybe once a year or something on that order), but it does happen. It's actually really nice to see that this is something relatable - I've never really spoken to anybody about it.

Can I join you? Would that be okay? I'll just sit down here in the passenger seat, and relax a bit. Whatcha watchin' there?

I have never seen this... is this some american thing?