Anyone who has ever taken their special needs child into public especially when they were young knows all too well that they were being judged by standards their child didn't have a hope of meeting and without being given the chance to explain we just had to look the other way - why is that 5 year old still in a stroller and not walking ( because I am trying to put off the expense of a wheelchair as long as I can) - why is that child making that funny noise (because she is non-verbal and can't speak and needs to indicate a need somehow) ......etc. As a parent you grow a thick skin and well my child who is now 20 years and only barely acts like 20 months is oblivious thank goodness to what goes on around her.
As with anything we need to stop and think about a situation before we react and if the world did that a little more it would be a nicer place for everyone.