What I have to ask is whether the people in these photos, even the very "soft-core" ones, know that their pictures are being shared over the Internet and used like this. Did they give consent, and did they understand the full implications of that consent? Did they get paid? Did they sign a contract?
I think I'm opposed to this kind of thing because I'm a libertarian. I see it as exploitation and deceit and privacy violations levied against people who are too young to understand or that cannot defend themselves.
I've debated people on this topic once before, and it seems to me that there are a lot of cyber-libertarians that will go straight to the mat to defend privacy rights except here. Why don't eight year olds have privacy rights? What if your doctor photographed you, told you it was for medical purposes, and then posted the pics to a gay porn site? What if a TSA screener posted millimeter wave video of you (essentially naked) to YouTube? Isn't this a lot more invasive than Facebook selling your friend graph to a marketing company? Yet most people would find that very invasive and deceptive -- a violation of their rights -- if they hadn't given consent.
And no, the dark stuff is not wild conjecture. I understand that the majority of pedophiles wouldn't be into it, but it certainly does exist. Over at Reddit /r/onions I read a while ago about a forum that exists on the Tor darknet called "Violent Desires." There were lots of "I cannot un-see" kinds of comments, and many warnings about "do not go there... you do not want to know." Child trafficking is quite real as well. The world is absolutely filled with unbelievably dark stuff (in other areas too) that normal people sometimes have a hard time believing: torture ("extraordinary rendition"), blatant fraud to the tune of billions of dollars, human trafficking, slavery, off-the-books unethical human experimentation, and so on... My experience in other areas of life suggests to me that the reality is probably worse than I care to imagine.