Not too long ago in human history (and even today in some places and with some different forms) it was customary for young boys to orally pleasure old men, or wed off girls before or at puberty. Playing more devil's advocate, the only thing that should really be illegal is exploiting children when they can be shown to be incapable of sound personal choices. (So covering both child porn and Britney-Spears-pattern Disney stars at once.) Now we just have to worry about where we draw the line at exploitation and whether potential monetary or status gain is important or not. The main point though is the act has already occurred by the time some pedo sees it on a tor page, and I don't think it's ever been shown that pedo-consumers are much more likely to become pedo-producers if they weren't already. (Someone please correct my belief if that's not the case, and then explain Japan.) Of course, catching either the consumers or producers is fairly difficult without draconian, invasive practices, and on the producers side it reduces to the classic problem of domestic abuse.