Well, from my experience with family members and friends I think that one of the main reasons that religion is so popular is the sense of security that many gain from believing in god. When I have discussions with my Christian friends they often ask me how I can live without the feeling of happiness and comfort they get from believing in god. They seem to think that living without belief in god would be frightening and unpredictable.
I think that for many believers the idea that they might be wrong is scary to them because they have always had the feeling that they knew the truth and were comforted by that. Fear of having that certainty taken away is what I think drives many believers to ignore and avoid evidence that goes against their beliefs.
If ten thousand persons with Ph.D.'s say porn does not harm kids this means they are secret pedophiles and brazen liars.
-Willowtree