You've done the right thing, a person like me would've just looked the other way and as for what I think about people like that, it's just life in my opinion, maybe they had their reasons, maybe they didn't, I try to not let it bother me. In one scenario, my neighbour used to have a pair of dogs which I've known and played with since they were puppies that he neglected, He kept them fed, but he never really cared for them and they were always roaming the streets, eventually, one was stolen and the other was chopped in the head and bled to death, during the time they were alive, he always tried to give them to someone else,repeatedly offered them to me I could've stepped in, but I just didn't really care all that much, in my opinion they were just animals and would've been a hole in my pocket since I'd have had to pay for their food and whatnot myself, In a way you could say that I'm just like those people, At the end of the day, they're just animals that will be dead before you know it anyway, so no point in having too much feelings for them, perhaps that was also their mindset. Just giving my honest opinion, though I own three dogs now and I love all of them but if something were to happen to them I really wouldn't care. Hope that made sense there.