only half-right :-)
I believe in the basic goodness of animals. Animals have no concept of right or wrong(as we know it, anyways). The "bad" things they do, like biting someone, are done only because they think they need to do these things in order to survive. It isn't out of malice.
Human beings, I believe, ARE capable of doing things they know to be wrong, out of sheer cussedness. Evil is real, and it lives here among us.
The transients normally don't belong in an "evil" category. They are displaced, needy, fractured human beings. That is why I say, if you give them some responsibility --ASK for their help, don't wait for it to be offered, you might be surprised. You will CERTAINLY be disappointed too, but isn't that already par for the course?
Yes, I think what you saw on TV was part of that program. They have a series on it right now, called "Cell Dogs". I haven't seen it in quite a while because I don't have TV right now, but when I was watching it, I was deeply moved by the way the relationships with the dogs helped to graduate the men out of their self-pity and feelings of worthlessness. Check it out. MAYBE something like that would work with the homeless, as well. I believe that if it were handled the right way, you would have some startling results.