It's true, Shaq has always done a lot for the community, and a LOT of it doesn't get any press (like it does for David Robinson). Shaq has ALWAYS been like this.
Shaq offering to pay for Mikan's funeral does not surprise me in the least. He's a standup guy, and from what I hear, Mikan's family is very poor. And to note, Shaq and Mikan were friends, and became very close during Shaq's years with my Lakers.
Now as far as his soundbites to the press? Think of it like what Ali used to do. He's says a lot of just to get a reaction from everyone. He's basically having fun with the press, the NBA, and everything in his surroundings (like the MTV Cribs special that they did at his LA house).
Like TimVP said, some people are just jealous of greatness. When Shaq is done with this game, he'll go down as one of the top 2 or 3 players in NBA history. Lose the hate.