So? He's said many times throughout this ordeal that it was incredibly embarrassing, and how it sucks that the thing he's now most famous for is "too fat to fly".
Isn't this his fault for publicising it?
People on the plane recognized him and saw him getting kicked off. It probably wouldn't have been such a big story if he hadn't said anything, though.
The reason he said something in the first place is because he was pissed off/embarrassed by the situation. Tweeting ultimately made it worse, probably, but eh?