Ethically speaking: Ethical boxes

I guess you can call me a box collector. I save almost all of the boxes that we get from Amazon and put them in our basement. Whenever we send presents to grandchildren or other relatives, I pick out an appropriately sized box to contain the gifts. We do not buy presents based on the size of the boxes that lie in the basement; however, we have not had to buy any boxes, because I maintain an adequate inventory.