It's amusing, in a grim way, how many people think all wheelchair users can just get out and walk. Such users need to be careful how they respond in such cases, as there are those who will get quite shirty and bang on about "not being fooled".
Obviously the best solution is to ensure wheelchair users don't go out in public. Fans of the 1970s will remember how much better life was when they were kept out of sight.
(For the benefit of the dim when reporting the above,. you can let MNHQ know it was my perverse sense of humour being deployed to emphasise modern social injustice),