A lot of what is termed "belief perseverance" is actually a concept better known as Faith. Religious people act contrary to established "truths" at times because they are placing their trust in a higher power than the intelligence, logic and reasoning of man.
For example, in the Bible when Moses took over a million people out of Egypt into the desert the common sense of man's established truth dictated that they would all die of starvation or thirst. God, a higher intelligence than man, promised to provide for them if they would follow him. They followed, putting common sense aside, and were cared for for 40 years until they settled in Jerusalem.
Now, whether or not you believe in this account is not relevant to the point I'm trying to make. I use it only as an example of why religious people stubbornly adhere to their beliefs in the face of man's truths. They believe they are serving a higher being. Personally, I believe that the consumption of alcohol is something the Lord has counseled against and yet there are many studies saying that a glass of wine a day is good for your health. Who do I trust? Science or God? I make my own choice in this matter and you can make yours. Just don't get frustrated or angry when I or others striving to serve God don't change what we believe in order to suit the newfound "truths" science or men present to us on an almost daily basis. (live and let live) (agree to disagree) (bygones be bygones...)