DS has autism and it is hard for just one person to have him all day. Also having helps make the trip better for others around us. Believe me, you don't want to be shocked when my DS touches your bumm despite me telling him no 200 times, using time outs, negative consequences. He just like to touch.
It's at places like WDW that a parent secretly wishes that autism wasn't "invisible." DS has Asperger's Syndrome and has very few "issues" when it comes to Disney trips. However, I do remember on our first trip-I think he was 12-at the hotel, he didn't get the "social rule" that you wait for everyone to get off an elevator before you get on. The doors would open, and he'd attempt to get in, bumping in to everyone trying to get out. I'm sure that everyone thought he was the rudest 12 year old they'd ever encountered. I like to think that this type of experience makes me more tolerant of other people's kids...(but I'd probably still be surprised if your DS touched my bum. )