Where do they come from?

Sir
While driving through the town at night and sometimes even during the day, one can see many vagrants sleeping on pavements around the CBD.
Some of them sit outside shops, obstructing your path as you walk.
The question remains, where are their families or homes? Surely these people have someone who is supposed to care for them? Surely they have a back story as too why they’re on the street. And why won’t the police assist in removing them or finding them a place to stay?
As much as I sympathise with their plight, it is also an eyesore for the town to see them sprawled outside shops, even during the day.
Can’t something be done?
Concerned Resident