The reactions of his team-mates and manager to the bite might in some way explain why Suarez keeps doing shit like this. Everyone is rallying around him and calling him the victim. Even the press from his home-country have gone easy on him, and are instead trying to apportion blame on the English press. I think it says a lot about their society and the role football plays that they won't condemn such behaviour, and the reason? To keep their World Cup chances alive.
If you read the ESPN article about the Suarez head-butt in a youth game, the lengths his coaches etc.. went to to try and cover it up were incredible, just to avoid a suspension for Suarez in a crucial game the following week. There was no inquest as to why a 16 year-old kid might head-butt a referee or possible punishment to try to prevent Luis repeating this at a later, more important, moment in his career.
It appears as though he's had this cushion his whole life, with people around him trying to convince him that his actions are not bad, or even worthy or reproach. In that respect Liverpool was the perfect fit for him, as their fans have continued this life-long crusade to convince the world that Luis isn't a bad guy, but a mis-understood genius. It's absolute bollocks. He's just a cnut.