Comfort zone. religion is one gigantic comfort zone for many

Mostly because it takes no effort to stay ignorant. It takes effort to become educated.

Intellectual slovenliness in part, and it is easier to follow one's cognitive consistency. It sets up a Manichean universe of simplicity.

Being ignorant can be blissful....without need to know or care....having knowledge can be a drag and can sometimes require responsibility......

They are intellectually lazy.

Two major reasons: They believe in a political and/or religious ideology which denies knowledge and does not encourage one to seek knowledge, and/or (2) they are members of social group whose norms and behaviors punish people for seek ing and expressing fact-based knowledge.