l am not an important customer, I can leave or go to head office if I want to!

I went to shoprite 6:30pm, express tills are closed and only a few tills are operating and the lines are very long. I took 2ltr coke, cones and a tub of ice cream and I went to the cigarette counter which was empty. I put my stuff on the counter and the cashier is not doing anything, she said go back with your food and join those lines. I said why because it's empty here and are we not supposed to pay at any tills she then keeps quite and she ignores me. I asked her again the said I must buy a cigarette then I can pay! A lady walk in front of me then she purchased a 500ml of coke then she paid and left. I asked the cashier why did she pay for a coke and she was assisted and I am not allowed to pay? silent treatment then she said next customer. I asked to see the manager then a lady by the name of deliwe admin manager said. I am the 1 who is in charge there's no manager. I explained my story and I asked why are express tills closed early because we are told that the store closes at 7:00pm. She said you are not special and you are like any other customers you will never pay there, it's either you que on those line or you can go. I asked her that if that's how you treat customers she said yes those who don't want to listen. I said tomorrow I will contact head office/ customer care and then she said go ahead they will put you in your place! I was so furious I left the store and they laughed at me. I remembered that someone told me about hellopeter.