No Really People... I'm DOWN HERE! *waives arms above head*
On a certain level I knew that people who were different, that is to say not upright, walking properly, healthy, etc were treated differently. As a white male of decent means however being looked at as not "normal" or not even really a "person" was an experience that was very eye-opening for me. I feel I'm self-aware enough to say that with some level of certainty.
I realized it first when I started taking my first strolls outside in the wheelchair with the help of my girlfriend. We live in downtown Lexington, KY which is a beautiful city with a very vibrant and alive downtown area. The first (and this is VERY consistent) thing that I noticed was that no one looked at me. EVER. If I spoke to people they would find ways to avert their gaze to somewhere else, anything else really, just to not have to look me in the face. Even with some children that I coach, coworkers, etc... particularly the FIRST time they would see me in my wheelchair usually a little gasp would escape them and they'd lament how they really weren't ready to see me in the chair. That I, "..looked 'different' in the chair."
I realized pretty quickly what that meant deep down. Wheelchairs in our society are most commonly used by the elderly. I think that's the experience most people first have with a wheelchair... pushing or watching someone push and elderly relative in some hospital or nursing home. It was something that someone was in when they were at the end of their life and I strongly believe that is the deep-down-emotion that it brings to the surface in people. They think (maybe unconsciously) "this is a person close to death, or that has been close to death..."
I think we can all agree being dead sucks. No one even really likes the idea of dying... and I think that's what it all boils down to. Ultimately people don't want the disabled person to die (which is nice) but that makes them uncomfortable in dealing with you in general as you remind them of mortality with your mere presence. It's the same reason people don't feel comfortable visiting people in Hospice. I was once that kind of person but I can tell you that it doesn't hurt you to see those people what hurts you is NOT seeing those people when you can.
It's not just looking at you... but talking to you is apparently difficult for some people too. I think the big thing is for most people is whether or not to mention your disability. As someone who's been there, if it makes you more comfortable to know what happened, then BY ALL MEANS ASK! I'd much rather spend a few minutes explaining my situation to you than to have you ignore me for the duration of an interaction with you.
Finally, for the love of god, don't bend down to talk to me. I realize what you're doing, you're putting us on even footing... but trust me, it's not necessary. I know that you're doing it to make me 'feel more at home' or something along those lines, but really it just reminds me that we're different when I'm in the wheelchair.
I think what all people who are disabled want is to be spoken to like we're normal human beings and not children or somehow unable to understand the words coming out of your mouth. If you want a good list (and the source of the above funny pic) check out this link which has some other great things NOT to do/say to a person in a wheelchair.