I agree with you that those who have to use those carts would give anything not to have to use them. My husband needed one on our last trip in Feb, following a major back surgery a few months before. He got the ok from his doctor to go to WDW. He could walk clumsily due to nerve damage, and could not walk the length that is required in WDW. He would only use an ECV in the parks, and refused a couple of days! He said he would not inconvenience the people waiting for the buses by using one all the time. I could not convince him to do otherwise, so he hobbled and swayed to the resort and back, to the park entrances and back, every day.
I wish others would have to use an EVC for even a half a day and see just how much fun it is to look at others behinds all day while missing looking at the attractions/sites, have to constantly be on the lookout for people stepping in front of and stopping in front of his cart. Not to mention the looks you get when you park and walk to the attraction. Just my ECV 2 cents worth