They only read prohibitionist sources, and they believe whatever they are told, however absurd it may be. This is more demonology than ideology. It keeps the circuit closed. In the end, this will work greatly to our advantage. Generally, I think that it is unfair to cite an extremist position as typical, and then use that as the target of a rebuttal.
All movements have their crackpots.
Rebutting them really proves nothing except that you can beat up on the rhetorically-challenged. But among prohibitionists the official voices differ little from what in any other movement would be considered an extremist position. If you are prohibitionist, you can never be too extreme to be mainstream. Moreover, the media will never object. Below are some excerpts from various pages on the For Our Children's Children site.