Okay, so I'm obviously biased, but this really really fucking pisses ne off. This is abuse of the worst kind. They are taking the mentally disabled and made into an object to entertain people. If "normal" people choose to do so, that's up to them. These people are so easy to manipulate because of their disability that they can be made to do almost anything their parents haven't taught them not to do.
I have one, and I can assure you that she would never do this. Shit, we are looking at prom dresses now and almost everyone my wife shows me I'm like, uhh no. You find a damn dress that covers every bit of your stuff.