No I'm not blaming rich people here in particular, but the fact that people having certain crazy beliefs is often advantageous to some other people.

A (witch-) doctor is a good example. It is good for them that people believe they can deliver the cure. It may sometimes be even good for the patient because of the placebo effect.

People having non-scientific mind-set (i.e. people believing crazy things) is beneficial to people who try to hoodwink them. Snake oil!