How does not educating people benefit society?

Allowing people to continue to believe in talking snakes,2 people propagating the entire human race,people living in whales,humans living with dinosaurs,being gay is a 'choice',there is somebody watching everything you do to see if you are bad,and many many other examples of tolerated ignorance. I mean If you knew someone who was like 30 and they still believed I mean truly believed in santa claus or that fossils were put on earth as a trick by the devil. Would it be in that persons best interest to continue to believe such nonsensical things? Or would you want to educate them so that they wouldn't be sad when santa didn't show up or the benefits of why fossils are real and how they play a huge role in fueling our world and knowledge of the past?