We stay there for the same reasons that we stay at the Moderates or Values -- because the resort will enhance our vacation experience somehow.
For example, if we plan on doing nothing but lounging around our resort, we would pick the GF or AKL (the ambience of those two places just can't be beat). If we plan on spending no time in our resort at all except for sleeping, we woud pick any of the DVC resorts (BWV, BCV, etc.). If we plan on experiencing something completely new and different, we would pick a resort that we have never stayed in before (currently, that leaves only the Dolphin, Beach Club, AS-Music, AS-Movies, Fort Wilderness Cabins, and Polynesian).
There are other times we pick a deluxe resort because we have something special planned at it. For example, we have a private function to attend. It's easier to prepare for that function and attend it if we are staying on its property.
Then there are other times we pick a resort simply because it's our heart's desire. We always pick a favorite when that happens. You just gotta listen to your heart every now and then, ~sigh.~