Mmm, well I haven't watched the Kenny video so it's impossible for me to judge on that one.

But I have seen stuff on YouTube which has purported itself to be 'funny' and which is actually just 'funny' because the owner thought it was 'funny' to do stuff to their animals which terrorised them or otherwise tormented them: Drunk tiny puppies, hamsters spun on superfast wheels, arthritic dogs incapable of standing or coming to the owner when called. I don't look at animal videos on YouTube any more, because you never know what the content is actually going to be.
(I can't even watch crap like "Animals do the Funniest Things' because it usually features 'funny' clips of animals who are obviously disturbed or even have symptoms of some kind of physical disorder, that make them do 'wacky!' stuff' >cue canned laughter<)
So I sure as hell won't be watching the Kenny vid.

Unfortunately, much as I personally hate cruelty to animals, with all this material out there where animals are seen as furry objects to have fun with. It's a much broader cultural ignorance which is really the culprit, and again I feel that the particular boys in this instance, are possibly going to become scapegoats for our own cultures various forms of generally accepted cruelty, misuse and inhumanity towards other creatures. And scapegoating style witch-hunts - which fail to address core issues, are again, further dangers I see in any form of vigilantism.

I did however watch some news footage about the case.
And it is quite fascinating how the vigilantes tracked him down... Even creepy.