Spoke with an amazon person through their associate chat window feature. She was very clear that is not allowed to download product images, and serve them through your own server. Yet, I see every major affiliate website doing it this way.
Additionally, all of the major websites use the same images on all their social media sites too, and tons of them are cropped to specific og and twitter card specific sizes for easy sharing. The amazon person made it very clear this is also not allowed….