If you are the hiring manager and you ask the Person what they do on spare time and if they talk about attending church and doing religious things among other things, will your view that they can make irrational decisions cloud your judgment on hiring this individual ?Don't get me wrong, I'm not going around insulting people over this or anything. I actually prefer to know nothing at all about what people believe in for this exact reason. But if I found out that you go to church every sunday and say the Lord's Prayer for supper every night, I'm definitely putting a "believes in the supernatural" sticker on your file in my mental filing cabinet. It's probably not going to change anything about how we interact but it's still going to be there in the back of my mind.
It's probably a cultural thing too. I'm a Swedish and university educated, I can't come up with a single person I know for sure to be religious apart from some girls I went to high school with ten years ago. At best I've heard rumors about others. I get the imression that most people under 40 who aren't themselves part of some kind of revival movement over here have similar attitudes.