Why do religious people not study more religions outside their own?

Let me first preface this discussion by saying that this is not one about whether or not god(s) exist(s)...nor is it a discussion about whether or not religion is necessary/unnecessary, logical/illogical, etc.

This is a question to believers mostly but not only to believers. What are the reasons why many believers stay to the religion they learned from their parents and not, so to speak, ‘shop around’ before making their choice…and if you did look through your options when you arrived at your chosen faith, why do you not continue to look around as new religions arise…and if you rejected religion, why do you not look into it again in case things may have changed for you of in the religious community that you grew up in (aka maybe they’re now better about including women or LGBT people or doing more charity or whatever)...

Is it because religion is too huge of a subject to continuously study? what of the academics that do it with or without regard to their personal beliefs – what makes it easy for them to just be detached in such a fashion…I suppose an additional question is whether or not you can truly declare yourself of a certain faith or is it a life-long search/journey…and why you, specifically, have not looked outside your religion to read texts/examine structures/rituals of other religions…how can you be sure that your chosen faith is right for you and there isn’t a more suitable belief system someplace out there

p.s. if someone’s answer is ‘because I know mine is THE true religion’, let’s not start the hate speech, we have done enough arguing about this…just move along…