One: because fascist would ensure their place at the top of the social/political/financial pyramid.
Two: because the world’s economic system lied to them. Being a morally good, hard working human guaranteed a comfortable life. In fact being morally good and/or hard working may actually be a hindrance to living a comfortable life.
Three: poor education and exploitation. Ever book that is banned or text book that says, “slavery was understandable in fact slavers are benevolent leaders saving the ‘others’ from themselves.” and you know, being used by those that actually hold power. Donald Trump would pretend to be the next Joseph Stalin if it ment he would be protected by those willing to do violence in his name. Just the fact that governments have" heads of state" means those that want to be president, king, prime minister probably should be allowed to be leaders.