Wouldn't this be violating copyrights left and right? Presumably most of these listings have pictures and I'd be surprised if Amazon were asking permission to reproduce them. Would the same apply to item descriptions...?
No. The producer of a good has no copyright in images made of that good by someone else. Ordinarily, the photographer holds the copyright to an image, unless it was a work for hire.
So if I buy a thing, take a photo of it, then use my photo to accompany a listing for that thing, the manufacturer of that thing has no recourse in copyright law.
Search engines would have been violating copyright for the last 20 years.
The first sale doctrine allows for public of owned works for the purpose of sale. Otherwise eBay, used book store, and flea markets would all be massively violating copyright.