There's also the fact that the Heat do a couple of things that are important for most people who play or have played basketball in any competitive capacity.
They win most of their games, and they play fun basketball. And they do it in a warm place with a great nightlife and no income tax. And as close of a guarantee of a long post-season as you can get in a league like the NBA.
And you get to play with the best player in the world.
It's the doctor J effect:
Teammates speak of him with healthy degrees of awe and camaraderie. Marc Iavaroni, a marginal forward cut by a couple of lesser NBA clubs before catching on as a "role player" in the Sixers' system, says, "Playing with the Doc? Don't pinch me, please. He looks for me. On and off the court. Can you imagine that! Dr. J looking to pass off to Marc Iavaroni? Know how that makes me feel?"
As said earlier, especially if you've already got a ring, why wouldn't you want to play in Miami? It sure beats the heck out of slogging your way through a 35 win season in some miserable place like Minnesota or Milwaukee.
Also, based on the exact wording of the quote (starting and ending with 'of course') and the location of the interview-prior to the kick-off of Game 2, makes me believe that Thomason (the fox reporter) asked him something like
"Any chance you'd be interested in signing with Miami?"
And then laughed himself all the way to a newly-minted headline.