That's awful/disgusting. I always stop and pick up dogs when I see them out and about. Poor things. I think if I had a big backyard I'd have many many pets by now. If they don't have numbers on collars I usually end up walking the streets or driving around until I find their owner.
Just can't believe some people, that they can deal with not stopping. It's illegal to leave a dog on the road if you hit it here. Cats for some reason you don't have to stop though.
