Mocking clients

Disgusting service. 7:45 last night at Broadacres KFC I was treated shockingly. I was super friendly and polite as I treat everyone in my life: how was it returned...well I overheard the kitchen staff mocking everything I said, repeating my sentences and mocking every word, all of them having a fat laugh. The lady that managed the card machine turned around and said she is sorry for the kitchen staffs behavior... not to sound pathetic but I left in tears with the way they were going on... who treats clients like this....KFC does.