Well, one topic which is covered in some detail when you are screened for security clearances is precisely how you use alcohol (and other intoxicants!).
It’s perhaps wrong of me to generalize but I’ve lived in Utah my whole life, some are clean and healthy others are unhealthy slobs, just like the general population. The whole ‘drank all the booze’ people are more often those pretending to believe in their faith because of the social repercussions of leaving it.
I imagine it is for this precise reason.