To clarify, this is a consumer protection law which is set in all EEA countries. Discounts are regulated to prevent stores from tricking their customers into thinking they are getting a product at a lower then usual price. You can only claim a product is on discount if the price has been lowered from a previous price less then x-days ago (I think 2 weeks is not uncommon), after which this discount becomes the new price.

As a European immigrant to the USA, it infuriates me to no end that American stores are allowed to use the words “price” and “discount” interchangeably. When I get things “on a discount” I expect to be paying lower then usual price.