It’s summer, and in addition to spritzes, terraces, the beach and the songs of the Magic System, the warm season comes with another must: festivals and concerts. The opportunity to drink shots from reusable cups. But if it is normally possible to bring them back safely to recover their deposit, this is not always the case, far from it. We then find ourselves with mountains of glasses on the ground, where the crowd was pressing. Where with cups gathering dust in the kitchen cupboard.