Shocking and bad attitude from cashier

I was @ pick n pay Bedford in the queue waiting to be served when out of nowhere a client jumped the queue at their cigarette counter, when I asked the cashier by the name of Mpho she became all ****y with me saying the client was in the queue.I then asked her as to why would I question her if the client was in the queue and she kept quiet claiming not to understand what I'm talking about.Does pick n pay offer preferential treatment to other clients? if that's not the case then I truly believe that I deserve a formal written apology from the cashier concerned as well as from the store manager because the bad attitude I got from your cashier is disgusting.From a very worried,concerned and loyal pick n pay client.