Crying in a parking lot

Our son has a very rare disorder and has global delays; he uses a wheelchair for mobility. He loves to eat at restaurants. We have tried to go to a local place three times - twice we ate in but not without having to ask for a manager to assist - the manager didn’t come talk to us nor did it make the visit any more welcoming on their behalf, but twice we actually got a table. The place has had a couple of incarnations since a chain moved out. There is a ramp to get in - the main dining area is high top bar height tables - not accessible for a wheelchair nor safe for our son to sit at. There is a standard table height area in the back that is often empty and roped off for groups, which often only take up part of that area. The times we have been seated there (there is nowhere else for us to sit with our son) it was an ordeal, we were turned away while empty tables were in sight, and then begrudgingly seated. Second awful experience - cashier at a large chain store trying to get my son to respond to her - I explained that he has cognitive delays and is non-verbal - she continued to try to get him to respond to her the way a “normal” child would - and when he didn’t she called him rude. I explained again, fighting back tears, that he is not rude, he cannot speak and has delays that make it so he can’t respond to you like an average person would. She KEPT TRYING ANYWAYS AND CALLED HIM RUDE AGAIN. I made it about three blocks before I had to pull into a parking lot to sob. I called that store and told the manager what happened, saying I think she needs more training. He apologized profusely and said he’d have her pulled from her till to explain to her what she’d done.