They aren’t all the same, for starters.
I was at Ft Washington Men’s Shelter at 168th St in Manhattan in 1984. It was a massively huge room. As in “if you leave your cot to go to the bathroom, be sure to count how many cots you pass before you get to the aisle, then how many rows you walk past on that aisle to get to the door”. They didn’t turn the lights off at night. Place was full of smoke detectors whose batteries were past their prime and making those annoying high-pitched “change me” chirps. The security guards yelled and threatened with their batons. It was very anonymous, like being a homeless cat that some crazy cat lover would let into the garage and set out cat food. In the mornings we were turned out. There was no vestige of permanence like being able to have the same cot or a locker to keep stuff in or an address where you could receive mail or a phone number where someone could contact you.
My upgrade from that place was the shelter on Creedmoor Psychiatric Hospital grounds: the honchos had decided that homelessness was “caused” by lack of services to the mentally ill and the money being thrown was being thrown at doing something about that problem, somehow, so a social worker told me they’d be looking for success stories and since I had a psych history I should parlay it. This shelter let us have a permanent bed assignment, a locker to put stuff in, and we could receive mail. It meant being able to fill out applications and leave a way someone could get in touch with me, and I got myself enrolled in college from there. Wasn’t all roses though, the security guards were far worse, much more violent, scared shitless of what we crazy lunatics might do.