I think there’s some confusion with how the product works:

The images are scraped on behalf of user request along with relevant information from the originating webpage. The goal is that all pins on Pinterest are actionable (in nearly all cases, linking to the original webpage). The most often cause of missing links is for a website to go offline. In those cases, would you rather your Google image search return no results or for a cached image on Pinterest with a link to the original website which can be used for further digging.

> (probably violating the copyright holder’s rights in the process)

No, that’s not what is happening at all here.