To answer your question..... Well, why push castration and genital mutilation on children? Why push the next generation of females into sex work? Once you realize this is about real metaphysical evil and that this is about satanic activity, you realize they harvest it from children because it gives them pleasure to inflict pain on the most innocent.
It does exist as a synthetic compound. See here: https://en.m.wikipedia.org/wiki/Adrenochrome.
To answer your question..... Well, why push castration and genital mutilation on children? Why push the next generation of females into sex work? Once you realize this is about real metaphysical evil and that this is about satanic activity, you realize they harvest it from children because it gives them pleasure to inflict pain on the most innocent.