The really sad part is that most of the folks on the streets are truly unemployable. They're homeless because, quite frankly, they have a thin mental grasp on civilized society. A large percentage were released from mental institutions either because the money ran out or the institution needed the bed space. And most of them are alcoholics who may or may not have been productive members of society before drinking their brains away. I read somewhere that the average lifespan for a vagrant is 3 to 5 years, some more, some less, depending on temperate climates, local welfare codes, and food supply.
Here in Florida, we get a lot of vagrants hitchhiking down the Interstate, hopping a train, or generally ho-boing their way south for the winter. A lot of them congregate in the downtown sectors because that's where the soup lines are. Where I live, the bums usually sleep under the bridge onramps and highway overpasses. A few fortunate ones get to sleep on (and sometimes under) concrete benches with a spectacular view out over the bay. I pass them when I go jogging. They usually keep to themselves, just staring out over the water like the statues on Easter Island. I avoid making eye contact, and keep my eyes on their hands, and with my pace I'm only within casual earshot for a second.
If it were up to me, I'd move the soup kitchens out of the city. The hobos will go wherever there's a steady supply of food and shelter. If they want to camp, they can do it in the woods instead of in the concrete jungle.