not sticking up for fat people, but you can be disabled and still walk. that's most likely the case if you are using the store's scooter, and not your own chair (and most wheelchair users are not completely paralyzed/unable to stand or walk at all, too).  i have rheumatoid arthritis and walk with a cane. sometimes if one is available and i'm in a lot of pain, i use the scooter. when i need to get something off of a high shelf, i stand. sometimes i use a wheelchair if things are particularly bad, but i don't always need one (and sometimes don't need my cane). i get confronted A LOT by people accusing me of faking and saying i should be ashamed of myself because i look able-bodied/healthy. i agree that fat people are lazy, but the idea that people who need mobility aids are 'liars' if they can stand or walk at all is really damaging to all disabled people, not just fats.