Amazon can somehow put those displays in a Kindle for what... 90€? Maybe they have some mix-calculation going on with book sales, but in comparison a Kindle should cost around 400-500€ when looking at those numbers here.
Right, Kindles presumably have a high attachment rate (owners buy more ebooks) so Amazon can subsidize based on that attachment rate, and also the base model Kindle prices include direct advertising subsidization. (Check the "without ads" SKUs prices for something somewhat more comparable.)
Don't forget too many of the screen prices above are essentially single screen "retail" prices and Amazon would likely have better bulk wholesale prices worked out in their supply chains.