> However, why not just tag each individual item with the supplying vendor as it arrives? Amazon does track the original source of the items it fulfills alread

> However, why not just tag each individual item with the supplying vendor as it arrives? Amazon does track the original source of the items it fulfills already. See e.g. Amazon comment in this article: https://ftalphaville.ft.com/2019/04/03/1554287401000/Amazon--sub-prime---Part-II/ https://ftalphaville.ft.com/2019/04/03/1554287401000/Amazon-... > The system is purposefully designed so that similar products are not placed next to or near each other, and Amazon can also track the original seller of each unit.