I have been meaning to reply to this for a few days. Reading the self-righteous comments from people who are probably proud of themselves for hurling "descrimination" labels at the OP's theory and who compare any alternatives for the disabled as akin to racism without thinking about the people involved aggravate me. My father is a 70 year old veteran who only has one leg and cannot wear a prosthetic and can only stand on his other leg with a walker for about 5 -10 seconds max. After having helped him through vacations over the years, I can tell you we would love a chance to have a shuttle just for wheelchair families. Making life easier and less stressful for us would be a good thing. It is not like saying he can't eat at a certain restaurant or get a certain job because he is in a wheelchair. That is preposterous. (sorry I am not good at adding quote inserts yet so just look back at that poster)
Whenever we are in a crowded situation, our family has to make a formation to help him navigate through the hordes. He is definitely one who tries to say "excuse me" over and over and not run into people. But others act like he is either a piece of furniture or invisible. They constantly move right in front of him and if it weren't for us, he would never get through. Even at my son's graduation, we had to work together. If we are at the zoo or aquarium, everyone crowds in front of him at an exhibit the second a spot opens so we have to create a zone to get him to the viewing rail.
Anyway, if Disney said we could reserve a time (we already reserve everything short of toilets as it is) for wheelchair pick-ups, that would be a good thing, not a bad thing. The whole situation would be less stressful for everyone involved. We wouldn't mind standing up around him on the bus if it only had room for 4 or 5 wheelchairs, for example, and all family and friends stood instead.
Of course, it comes back to the same problem, they couldn't get to the parks faster than regular buses or the cheaters would move in for the kill. We would be o.k. doing the regular line while he rode the wheelchair bus and we met up with him at the park. I think the separation for 20 minutes would be worth his ease in travel. I have a feeling truly wheelchair-bound people don't want any shortcuts at all, just courtesy.