You can also commit crimes in novels or roleplaying games that are illegal. That's different from supporting a market that causes child abuse.

Possessing digital/virtual information that required abuse endorses abuse. Entropy is our friend here; only an extremely rare set of bits results from child abuse. You won't just find it.

Even fiction or photoshop is illegal. Your argument is much more applicable here, but seeing how society treats even inactive pedophiles as criminals rather than sick, I don't think it'll be very popular.