Bad customer service

I went to McDonald's in Rustenburg CBD only to get the worst service by Judy and Nelly, the refused to assist us saying that we must use the self service machine, the self service machine is optional hence there are still tills. First of all the self service risk as the POS machine is exposed and anyone could see ur pin and secondly there was anyone there to assist. There are many McDonald's where they give you the option to buy at the till or at the self service it should not be forced.