Actually, it's kinda simple. Renderotica is aggressive in dealing with copyright issues. I don't know if the old threads are there, since Diane sold the site and things changed again, but there are years worth of threads where someone finds something, posts and asks if this was allowed (usually with links), and if it is identified as from Rotica, the copyright owner is contacted. I also know that there was some guidance if it was needed. And it isn't just one or two 'copyright nazis' doing this; most of the folks at Rotica do a good job of covering each other's backs Plus when it comes to content, they tend to come up with traps, not barriers. They can't stop it, but at least two or three introduce anomalies that can be traced back to a specific purchaser.

No, they don't send knee breakers out on courtesy calls, and they certainly have no affiliation with the sites mentioned (as a simple trace can show).

Part of the reason for that aggressive stance is pure survival. The simple truth is that you can leech something from here, and who the hell cares among the parents, law enforcement, etc. But let 'adult' content get away from you, and be unable to prove you chased the perp to hell and back the instant you discovered it, and you will most likely find yourself shut down by some pinheaded DA looking for a soft kill to bolster their chances at re-election. Then there is the fact that they work hard for a smaller market, so that makes it even more necessary to strike quickly.