He's a well developed baddie. A great sarcastic personality. Even though we - or I, at least - don't root for him in the film, I certainly don't dislike him overall.
I can see how people go a step further and will feel sorry for him, as it seems that somewhere along the line growing up he felt like an outsider which turned to the worst of revenges. It's about giving the characters a little more consideration after watching the film, really.
Once again, I'm pretty sure most people don't
hate the hyenas. Hate is so strong a word, anyway. I'm sure no one has shown such a distaste for these characters.