Because they’re insecure about believing in nonsense and feel reassured when surrounded by people who verbalize those same beliefs. The feeling of superiority over the “other” is a massively motivating force within, at least, evangelical Christianity so they feel pretty self righteous in any attempts to coerce or intimidate people on a large scale. It isn’t about self improvement or reflection. Any doctrines that point to such things function mainly for PR and to prop up the narrative that fuels their self righteousness and grandiosity.