There is a big correlation between homelessness and mental illness, personality disorder, addiction or a combination thereof. So yeah, excuse me if I don’t want to deal with the paranoid schizophrenic hobo who’s high on god knows what.
I can’t speak for the US here, but in most civilized countries there is actually help available for homeless people and enough social systems to ensure that well adjusted people don’t end up homeless in the first place. With the homeless that we do have, the difficulty usually lies in reaching them, getting them to accept the help that is available and having them durably make the necessary changes to their life to escape homelessness.
Accepting some of their anti-social behaviors is actually enabling it, and not helping them at all.