To be fair, he (maybe) has to practice too. Plus, I'd like to think if I was as good as Kobe is at his career choice I could probably have a pretty sweet payout. If you're one of the best people to ever do what you do for a living, I'd imagine you could make a few million.
Not sure where I read it, but it said that Kobe is worth something around $75-80 million in revenue a season for the Lakers. So you can argue that he's actually underpaid.