Staff told us to get cup from bin when we asked for water

I went to kfc newtown on the 15 December 2018 we bought food and while waiting for our order my younger sister asked for water to drink with my daughter who is 11 years old. We were told by their staff on duty that they dont have cups, we asked for disposable cups they using for sodas and we were told to look for used cups in the bin they will fetch water for us. I told them that was not on but they said they cant help and they really gave us water with a used cup from a bin because my daughter was very thirsty. Your staff lacks professionalism and customer care. If they dont mind to advise a customer to use a cup from the bin how hygienic are they when handling food. I'll never advice anyone to go there.