I can’t speak to San Francisco, but I recall some of the youthful panhandlers in Portland, OR as being pretty damned aggressive, and that would’ve been in the mid to late 1990s.
I’ve heard from friends still living there that the streetkid panhandlers are even more aggressive now, just shy of outright mugging people.
According to what I read, a lot of them are from middle class families in suburbs. They don’t have to be there by any means, they want to be there. I just cannot fathom that. Wanting to sleep on sidewalks where the concrete is the toilet. They set up in front of businesses and the clients and customers have to pick their steps through urine and feces, the cops can’t make the panhandlers leave.