If I were trying to describe it in more flowerly terms: It's asymmetric information war fare.
The stores tell you they are good and benevolent and only have your interest at heart, so here are discounts. Discounts for everyone. They even gamified the whole thing with stickers. I shit you not. People collect stickers they put on the products in the convery belt at the register. There's also apps, which will give them all info on you
In reality it makes it impossible to know how much things cost