The total addressable market for heroin and cocaine consumption is demonstrably high. Kiddie porn demand will never reach this level, and hiding a sex slave in your house is difficult.
In Japan there's a whole (legal) industry that would be probably classified as "kiddie porn" distribution in US. It's certainly bigger than the local cocaine and heroine market.
You'll be happy to know that freedom of expression is slowly being crushed in Japan, just like everywhere else, so you won't have to feel creeped out much longer.
The UN's obscure subdepartments can demand, but Japan doesn't have to comply. And considering the size of the market for hentai, I don't think it's going to go away any time soon.
The total addressable market for heroin and cocaine consumption is demonstrably high. Kiddie porn demand will never reach this level, and hiding a sex slave in your house is difficult.