We have a Salvation Army Store near-by, but they never have anything useful. My daughter gets blankets for her dog very cheap, so she just throws them out when they get dirty or chewed up. I read somewhere that they sell items to other charities if it is something that they don't carry. They also ship to other outlets if it is something that doesn't sell well at that particular store. That's probably what they do with the items after they are picked through.
Sue