Not all the children, just Silver Shamrock wearers. I think we can all agree that anyone who succumbed to SS's annoying television jingle deserves what they get. Or, you could just keep repeating to yourself, "it's only a movie."
It was never intended to have anything to do with the first two. I love everything about it. All this talk of it being silly, is silly. Are we meant to think the first 2 weren't silly?