Undocimiled or Urban Refugees usually works, along with junky, grifter or lay about.

I just call them trolls. They live down by the creek, under the overpasses etc. the overwhelming majority are mental cases and/or dope addicts. If 99.9% of them the disappeared off the planet would anybody care or notice ? Not really

I work in San Francisco and step over them and smell/see human waste daily. Follow the money. The homeless industrial complex has so much money going to it that the business around helping the homeless is big business now.

don't get me started on the Veterans that spend 26 months over seas and come back to find out that their spouse and kid has moved out,
there house is being re-poed and
and claim that they can't sleep, go out in public or
get a job.

It's the Vets hospital's fault
It's the Vet's hospital's fault!

I gotta wonder how many would be out there if American's were taking care of the people who
sacrificed.

The term "Hobo" needs to come back.

Though, really it's attached to history as associated with the railroads, but I like the word.