Shared.com is in the business of producing and distributing crap content. That's a subjective term, but it's like the supreme court ruling on pornography, you'll know it when you see it.
These guys most likely "skirt the line" to just operate as a mediocre and crappy content distribution network, that at scale, makes a lot of money because there is a certain subset of the population that will eat up any content at any quality level.
Facebook decided they don't want to be a part of this type of content distribution, and they made a conscious business decision to not to engage with it's owners and operators because it will simply result in an exercise of splitting hairs and a reduction to the ridiculous. They just aren't going to bring themselves down to the level... and I don't blame them.