When we lived in Mesa, AZ there was actually a place behind a convenience store not far from our home, the store had put chairs and tables and a porta-potty for these guys to hang out while waiting for work.
They were harrassing customers, hanging out in front of store for a long time till the complaints and lack of customers had the store react.
Can’t say they were all illegal but......
Not uncommon at these convenience stores. This problem is deeply embedded and will require a tremendous effort to get under control.