GRRM enjoys the attention of being an author.
Even if he does, so what?
Have you every looked at his website and see just how many appearances the guy makes? He loves being fawned over.
Or, as a long-time member of fandom, he loves being part of the scene and knows that some of his fans enjoy interacting with him as he enjoys interacting with them. Where's the harm?
And the convention and other appearances (all of which are promotional work that's part of being a successful author, even if he enjoys it too) typically add up to three or four weeks a year. That's not an uncommon amount of touring for a popular writer to do. A little more generous than an average worker's vacation package, maybe, but not exactly an orgy of time off either. And in 2007 he canceled his trip to Worldcon and associated Japanese appearances... because it would mean too much time away from his writing.
He doesn't sit down and really crank out page after page.
Are there only two ways of looking at this? Does he have to be chained to his desk, producing pages, eight hours a day, five days a week, fifty-two weeks a year, for people not to raise questions about how devoted he is? I hate to be the guy who says this, but: it's only a book. He doesn't have to become a hermit for our reading pleasure.
Shouldn't it have taken less time? A lot of the stuff was already written...
Since then, he's reworked chapters that were "finished" because he wasn't actually happy with them, added characters to better tell the story, and reorganized things so the book works better on his own. Basically, he was way too optimistic about how close to finished he was, like he's been since he started the series. That's the one thing I don't like about he deals with fan curiosity: he backs off his promise not to give estimates about when he'll be done, and then the estimates are wrong again, and tears and recriminations follow.