Some people would argue that these kinds of people are actually providing a service -- they pick just about everything up off the street and try to recycle it in one form or another. Stuff we call trash, they call knick-knacks. Most stuff they can sell at a recycle place and get some extra cash. Yes, that's all good and everything, but I'm of the opinion of the other side:
They are noisy and I'm tired of them digging through my garbage bins to find extra food or to see if I've thrown away anything that might be of use to them. Seeing as how I eat everything I fix or make, I don't tend to throw away food... unless it's gone real bad/sour/rotton. I hope these people aren't eating that stuff. And considering the type of pack-rat that I am, I don't think they'd find anything too usefull as a temporary piece of entertainment.
This last summer, it seems like I'm constantly hearing grocery carts passing under my windows, going one way or another.
I don't know what's worse; the street people, or the ice-cream trucks that drive around, rain or shine.