It turns out that the mechanisms like "Buy more - you will get a discount" are popular not only in Poland but also in France.
In the picture you can see the promotion "Buy two pieces - the second one you will get with a 50% discount". That kind of promotions are very beneficial for a Retailer for several reasons:
We often talk about the differences between Poland and "mature" countries, but the principles of trade marketing refer to the psychology of human behavior, meaning they are much more universal than we think.