Unfortunately, that's probably how those unspeakable, excremental excuses for human spawn were raised. With a little luck, maybe the judge will order them to be tried as adults. Assault carries a bit more weight than malicious mischief or a lesser charge. Talk to the DA. This really needs to go on their permanent records because we all know they're going to do this kind of thing again, whether to you or someone else.
Pits, if there is an active humane organization, Pit rescue or animal rights organization near you it might be well worth it to contact them and see about filing a civil suit against these boys and their parents - not so much for the money as for the example.
I'm worried, too, that this could have some lasting effects on the dogs. They may never trust a stranger again, and Zeus, especially may be over protective, particularly when he's in the Jeep. You'll probably have some work to do desensitizing them again.