Jason Reilly said
11 months, 3 weeks ago: Hello @annfurnivall,
In my limited understanding Pinterest, and other sites that are known as content aggregators (i.e. theChive, FunnyJunk, Huffington Post, BuzzFeed, YouTube, Reddit, etc), have certain protections under the DCMA (known as the Safe Harbor provisions), that as long as certain rules and laws are followed, prevent them from being sued. However, having complicated and difficult gates surrounding user interaction doesn’t benefit them. So they make the process simple, provide for take downs, and hide behind ‘caveat emptor’ when it comes to consumer interaction.
So, in the minds of Pinterest and marketing companies that have a stake in pushing social media marketing, giving out long lists of what NOT could inhibit user adoption and buy in of the technology. If people don’t adopt their service, then they don’t sign up, if they don’t sign up they don’t give personal information freely or allow the company to track interests that can be sold to marketers so that they can profit. Thus they say, “pin away!” And hope you don’t read the fine print (which in Pinterest’s case I do believe the fine print does point out the legal repercussions of using copyrighted material without permission).
Anyway, I hope that answer was clear.
As for what I think about the millions of YouTube, Facebook, and Pinterest users sharing jokes and images? I say it’s been done for centuries at bars, taverns, and camp fires around the globe. As someone who generates original content for a company that is trying to sell books (my second job) I LOVE when people start repinning my stuff… especially if it becomes sales of the book. But I’m a minority. Most content generators get very upset when they realize that someone else might be looking at their content, and might see a way to change it or make it better (Note: Up until recently this was protected as fair use, or we wouldn’t have five thousand different remakes of Shakespear’s Romeo and Juliet… some of which I wish had never been made).
I could go on forever about copyright, but I’m not going too! You guys do not deserve being subjected to a Jason Rant. 
Just my wife.
Jason