Perry's not a bad dude and is quite cognizant of other people's troubles, he shows respect.
The Sherdog prudes feel threatened by a guy who doesn't talk like they talk, walk like they walk, come from where they came from.
All of his wins were by finish, usually really hard and brutal. And he lost once by decision to a more seasoned fighter, who focused more on picking Perry apart than risking going for the finish. A losing Perry is still extremely dangerous.