I know I'm going to get flamed for this, but this is the truth and I'm gonna say it anyway!
At this one particular
Walmart we frequent, on any given day, we'll see numerous morbidly obese people riding around in the motorized carts, doing their shopping, while elderly people or disabled people sit waiting at the front of the store for one of those carts to open up. Could they ALL be disabled? I've wondered that myself. After years of shopping there, however, I have come to the conclusion that many of them just
won't walk in the store for whatever reason -- uncomfortable, lazy, etc. I have seen some of them walking back to their cars in the parking lot and the cars have no handicap license or tag hanging from the mirror.

I've also seen them walking along just fine in the other stores surrounding Walmart.
I am obese and I am uncomfortable walking, but you'll never see me taking up one of those carts from someone else who needs it. And yes, yes, I know that some of them may be disabled. It's taken me years of shopping there to discount the theory that they all are, so please don't insult my intelligence by suggesting the whole "hidden disabilities" issue -- I'm very quick to use that argument myself. Just trust me on this one.