Most supermarkets and stores/and malls have 20 plus handicap spaces to park in. It's a joke. One can sit there watching people pull into those spaces with the handicap placard, and no one gets in or out of their cars using wheelchairs or crutches. All seem to walk perfectly fine.
We always watch those that use these parking spots. Very seldom does anyone ever park there that actually needs to.
I understand what you are saying, but sometimes you can't tell a person's disability by looking at them. I had a dear friend who had a placard because she had respiratory problems to the point she could not walk far; she would just lose her breath. She got a lot of dirty looks for using handicapped spaces, but then her illness progressed to the point where she could no longer walk even short distances and had to get a scooter.
My husband has never gotten a placard, but is eligible- he can walk also; but only short distances. His legs were injured by a mine in Vietnam, as he ages his joints hurt badly if he has to walk far at all. My sister had one when she was terminal with cancer- you just really can't always tell by looking who really needs the handicapped spaces.