Worst still, I've seen Amazon produce a banner with the phrase "Dispatched and Sold by Amazon" - gives you the guarantee to receive original and genuine[2]
This means they know that other listings may not be original or genuine. So to solve this, they promote their own items as genuine, despite them owning the whole platform.
1. https://twitter.com/Martin_Adams/status/1169905424612507649?...
2. https://twitter.com/Martin_Adams/status/1305398394274414593?...