Really, possession and distribution of these images should be legal. Then pedophiles wouldn't feel the need to hoard it. They could easily get it online. However, obviously, the acts in them should be completely illegal. With the current system, pedophiles hoard images, and on sites like this, they'll want new material.
Much like the war on drugs, I don't think second-order effects have been considered in policy. Sure, law makers and most sexually normal people are going to have a gut reaction of disgust to child pornography. This leads to a knee-jerk "ban it" reaction. I think the "reasoning" stops right there. For every additional concept it takes to solve a test problem, you lose 75-80% of students. Likewise, I feel like lawmakers and the public have at least a 75-80% loss rate considering the second and third order effects of their policies.