Replace the Wheelchair Symbol with a modern non-disability specific image.

Supermarkets, shopping centres, stadiums, recreation centres - all of these are public places where many witness what they deem 'abuse' of Disabled Parking bays and/or Accessible Toilets. People become very indignant if people using either are not wheelchair users. It causes a negative view, which later becomes compounded by repeated accusations of, for example, benefit scroungers. Change the symbol. Produce communications that explain the reason for the change. Educate. Tackle discrimination.