Normally a decent store but after today I won't be...

Normally a decent store but after today I won't be going back. I was making a purchase and the power bars I was purchasing not only were expired but were a part of a crazy deal which I did not know. When I went to pay the cashier had to call someone else over to void out the power bars because of the crazy deal. Then a different cashier with purple and blue hair walks over and rudely tells me next time to separate them if I am using a separate crazy deal card to pay for items if there are items also a part of a separate crazy deal!..

She did not let me even say that I did not know there was a crazy deal on the power bars, and was very short with me. When she left I asked the original cashier to speak with a manager, she asks the woman with the colored hair to call the manager up. As I am waiting she has the nerve to ask me if everything is ok...

First off, I didn't appreciate that she didnt even let me say that I wasnt aware of the crazy deal then proceeded to talk to me like I am dumb. I work as a manager at a separate business so having known there was a crazy deal I would be courteous enough to separate items
Do not talk to your customers like that!! We aren't above you and you're not above us !