Bad Service

Went to shoprite (Zola) today the 01/08 while I was waiting in a queue I asked Palesa(cashier) why are we waiting so long, she was so rude she said to me I'm asking an obvious thing can't I see where this bus is heading I was shocked I even advised her Manager that I'm going to sort her out she didn't care service was so pathetic I need to know why I was treated like trash I should have gone to Pick N Pay,however I chose Shoprite. If I don't get any reaponse I will go further with this.