In my mind...whatever. At that time there wasn’t any reason for it. She embarrassed him and she embarrassed herself. He was not doing anything wrong and she shouted at him like a misbehaving dog. It was terrible behaviour on her part - and she was disruptive to the customers more than he was. The other cashier knew him by name and didn’t have a problem with him. It was 9 pm and there isn’t much around that isn’t several blocks away, where he could buy some cheap hot food to eat.Again, there could be a legitimate reason for him NOT being allowed to.
No wonder people on the street tend to have really low self esteem. Being treated less than human day after day would do it.