Consider the mechanics of being dunked on tho.
By the very nature of the play, the ball is dead upon completion, providing a natural pause in game action for all observers to marvel at the magnificent display of timing and athleticism. The ball might even hit you on the way down, and if asked to sign it, you probably have to.
Your opponent, now fueled by a rush of endorphins, can now stand over your likely fallen body and perform the pose of his choosing to the adulation of the crowd. He might even step over you AI-style. He can do no wrong for at least the next 2 possessions, and it'll be the talk of the town all day. It's essentially the combined appeal of a long-range jumper/fancy layup, a football sack and a spectacular ballroom entrance all rolled into one. What good can come of this? I can't imagine the devastation.
Yes, a sweet crossover pleases the crowd, but a lot of ballhandle types can't hit the broad side of a barn from the inside, so the two-part nature of that play often diffuses much of the potential embarrassment. I've never been fully yanked, but I've been left a few times in my day...then again, as a blacktop 5, that's kind of expected of me.
almost like magic or something. 
