Why is coke cheap in the supermarket?

Carrefour adopts the global procurement mode, so when negotiating with suppliers, there will be the problem of task rebate, such as the amount of XX thousand sales completed in the whole year. At the end of the year, the supplier will give Carrefour a certain fee according to the percentage of sales, so Carrefour is not profitable in some goods. Even if it is sold at or below the purchase price, it can still make money through year-end rebates.