Normally I like Outlaw's irreverent and sarcastic "fly-by" style, but I have to disagree with him on this one.
There is no correlation with below average intelligence and gullibility when it comes to joining cults of any kind. In fact, research (which is fairly limited) suggests just the opposite. Intelligent, creative people (that are unaware of the manipulative methods of control and coercion used by cults) are in some ways more vulnerable because their imaginative minds more readily fill in the blanks and missing pieces of the cult ideology when they are (unwittingly) becoming indoctrinated.
Couple that with an individual being in an emotionally vulnerable time, add some easy answers and a dash of hope and you have a new recruit. Voila!