Pick n Pay review: unethical behaviour

On numerous occasions, I find that I am being charged for additional large carrier bags, and it is now becoming habit, and beginning to annoy me.
My latest purchases, 04.08.2019 @ 13.07 at the little falls store. Cashier: temp cashier 31. I have decided, as this is the 5th time, that I have paid for an additional carrier bag, I am going to lodge a complaint, as it is unethical behavior and cannot be seen as an error. Different cashiers, all do the same thing, seems to me like you are training your staff to cheat your shoppers knowingly!