(Chicago), and let me first say that I've encountered similar passed-out, blanket-wrapped homeless folk sleeping on the streets for many years--long before the recession. I saw it back when I lived in New York in the 1960s and 70s.
Here's the issue: don't feel that these people are always being totally ignored or that there is no help for them. Many times they are picked up and taken to the many shelters and programs in the city, and they end up right back on the streets. For some, it is a question of mental illness, and though it's hard for us to imagine, they seem to prefer the street.
For two or three years in a row there used to be a guy who slept on the sidewalk under the train viaduct a block or so from our house, and no matter how many times somebody in the neighborhood had him taken to a shelter, he always ended up back there.
Our alderman told us that when we see a homeless person we should not give them money but place a 311 service call to have them taken to a shelter, because what they need is a warm bed, food, and counseling. There are a lot of programs here. It's getting people to use them.
I just say this to make you not feel so badly: there's a lot of tragedy out there. But there are many agencies, both nonprofit, religious, and governmental that do try to provide assistance. Unfortunately, there are always going to be people who are very difficult to help. And sometimes, agencies, though their intentions are good, are not able to follow through with people over the long term.
Shelters are not the full answer, because people tend to cycle in and out of them: permanent housing situations are necessary for gaining the stability to start to turn things around. Try to find a good agency for the homeless in Detroit and read about what they are doing in your area.