You must be new to the evil, deceptive world of marketing. lol. The "sale price" IS the "real" price and the "standard price" is a fake inflated price. The whole "sale" is fake. So all is fine. At least thats how it looks to me. I did not check out that solution completley. Just quickly skimmed it. But the sale prices are definitley the "real" prices.
It's the same as a used car salesman putting a $1200 price tag on a $900 car ... then giving you a "discount" (sale) and selling it to you for $900. The $900 is actually the "real" price of the car.