It sometimes feels like they encourage it by not taking measures against obvious fakes. Take a look at this: https://smile.amazon.com/TNSO-Certified-Lightning-Charging-C...

The "top reviews" are all positive, but all for different products (this is supposed to be a pack of Lightning cables) - phone cases, LG G6 accessories, a rifle stand - and it's the 4th product when searching for "lightning cable".

It looks like they can just completely change the content of an existing listing, including customer reviews, without any oversight.