Pathetic Service over a carrybag

Such bad service I've received today at Shoprite stand 4486, 111 Commissioner Street Johannesburg. Serviced by Bella Mdakane this cashier had the nerve to ask me in an accusatory tone if I had bought the carry bag in the store where I answered I brought it from home since I took it out of my handbag. I. Guess at this point she still was not satisfied clarifying to me and point that they also sell the same carry bag clearly I could see that as I had previously bought the bag at the very same store, then the starring contest began between Bella her supervisor/manager and me for a good minute these people starred at me for a carry bag REALLY.. A CARRYBAG.. PATHETIC I'm actually livid over this.. The icing on the cake her excuse or "reasoning" was that she doesn't want me to have an issue by the security when I'm leaving the store. Such ******* I've never had an issue for a CARRYBAG I don't need to declare a stupid bag she could have just continued with the transaction and let me leave the store in peace so that I can enjoy the rest of my day.