Religious and other dogmas need not make sense. Indeed, they may work better if they are not logical. Logical and useful ideas pop-up independently and spread easily, and widely accepted ideas are not very good badges. You need a unique idea to identify your group. It helps to have a somewhat costly idea as a dogma, because they are hard to fake and hard to deny. People would need to invest in these bad ideas, so they would be less likely to leave the group and confront the sunk cost. Also, it's harder to deny allegiance to the group afterwards, because no one in their right minds would accept an idea that bad for any other reason.

I more or less agree, I wrote something quite similar in "The importance of Not Getting The Joke":

Now, perhaps not so obviously, could it be people have some incentives to say and even believe or at least try to believe things that are obviously wrong even to people of their tribe (political/religious/ect. affilation)? Why would something like this arise? My mind at this point wandered to conspicuous consumption.

"Conspicuous consumption is lavish spending on goods and services acquired mainly for the purpose of displaying income or wealth."

Could there be such a thing as conspicuous wrongness?

"Look how much I identify with our group, I'm even willing to buy even if it dosen't do us much good. If I wasn't so virtuous I could never believe something this silly."

But why would sticking to the script when its blatantly false to others in the tribe boost your status and self-esteem? Well, sticking to it when its blatantly obvious to most people dosen'tcostyou anything now does it? Sticking to it when its merely uncertain only costs you the esteem of the out group (worthless in most cases)?