People who do believe in higher powers or the paranormal are one of two things.
Not understanding of the nature of the physical world.
Emotionally invested or socially invested in their belief system.
Almost always, and as was my case for a long period of time, I observe that it is the latter. We know and see that the world does not indicate any reason for higher powers, but fear the implications of that being false. What people who believe lack is only the culture and settings required to eeke them out of their views and into a place where they are comfortable exploring and changing the views that they hold.
These things, I feel, attach religion to people.
Fear of hell.
Abandonment of morality.
Abandonment of culture and family.
We fear the "infinite death and pain", that changes the weights and makes the cost-benefit calculation of following a religion skewed in religion's favor. We fear the fact that, without a God to guide us and show us good and evil we would be out there stabbing and stealing and murdering without guilt. We fear we'd be without help when others come to do bad things to us. We fear that our parents will hear our changes and see their child about to go to hell, about to abandon morality, a death more permanent than anything else, someone here to steal their eternal life, rather than their son or daughter who they love.
Truth comes at cost. To call those who cannot overcome the barriers I just listed as stupid, idiotic, or anything but reasonable is in itself stupid. Those who believe in religion are people held hostage by their culture and their fears. If you are an atheist and want to see them change, free them rather than belittling them.