The problem with doing that is word gets around and pretty soon the place is inundated with homeless.
This happened to a privately owned parking structure in my jurisdiction. It’s open 24 hours but between 11p and 5a it’s not used much. There were a handful of homeless that would sleep in the lobby during those hours and at about 445a a security guard would go through and wake them up and tell them to leave. The structure management didn’t have a problem with this until all of a sudden there were dozens of them all over the structure. Sleeping, puking, shitting, pissing on the floor, fighting, fornicating in the stairwells. The lobby and elevators started to stink to high heaven. They’d sleep in the elevators and when legitimate customers wanted to use them they wouldn’t move or would threaten them. We were getting called 3 and sometimes 4 times a night to clear them out because they no longer would listen to the security guards that came through there even though the guards were armed to the teeth. It became a nuisance call and the structure owners were advised calls there would take very low priority.
They’re working on sealing up the structure so only someone with a ticket or code can get it. It’s going to cost them hundreds of thousands of dollars because they let a few homeless “sleep in peace overnight" rather than throwing them out in the very beginning before the place got a reputation as a haven.