When innocent, non-food animals are harmed, everyone's first instinct is to start raging out the ass, and for good reason. Anyone that can just hurt something totally incapable of defending itself for their own amusement has serious loving issues. I'd go so far as to say that it's an evolutionary development to purge tribes of people that are likely going to be cut-throat and harmful to the rest of the pack.
I didn't actually watch the video because I have a soft spot for cats, and I have a morbid fear of being encased in concrete / buried / eaten alive. But from the sound of it, the dude has a history of dead animals showing up in his yard. That warrants some sort of investigation, but yeah, if they can't prove that he's somehow torturing these things nothing should be done.