Anytime a user pins an item that has a pre-existing affiliate link,
Pinterest uses a service called “Skimlinks” to swap out the original for its own. This cuts out the kickback to the original curator of item should a Pinterest user click-through and make a purchase.

This is not how you convince your members to trust your service. This is called lying disingenuous. Period. There is no justification for it. Pinterest should stop doing it and apologize. Anything less means users are being promised potential income only to have it removed without their knowledge.

Bad Pinterest.

[Update] I have calmed a bit and understand Pinterest is trying to monetize content. As a developer of social media, anything that monetizes your product piques my interest. However, as a blogger and user of social platforms, I would not want my content to be edited without my express knowledge. Pinterest needs money to pay the bills. I get it. I simply do not agree that editing user content is an acceptable method. Once users get the idea you edit their content, no matter how small, it will be part of their thinking process.

“I’ll pin this item at Amazon, because I just love it.”

<Pinterest_intervention>Let’s just change that to our affiliate id.</Pinterest_intervention>

<Pinterest_intervention>Second thought, we’ll make it Best Buy. They pay us more.</Pinterest_intervention>

“Hey, what happened to my link? I hate shopping at Best Buy. Why would I recommend them to my friends?”

<Pinterest_intervention>Meh. You got a free pinboard and we got paid. Move along.</Pinterest_intervention>

I know this is not what happens right now. They don’t change the retailer of the items, just the affiliate link. But, once you have convinced yourself editing user content with affiliate links is ok, you have no problems getting pitched as a channel partner for their competitors. After all, if Pinterest has become a huge traffic driver for retailers, who else is going to be knocking on their doors looking for partnerships.

Pinterest accused of replacing external affiliate links with its own | The Verge