Community
Job
In Laws
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Business standing and connections
Many atheists pretend to be religious for all of the above, and when coming out of the closet put one or more of them at risk. I've known people who were disowned, creatively dismissed from employment, bullied in school, had major marital stress due to righteous inlaws etc due to having their disbelief found out or for having lost their faith. For other atheists the risk of being known isn't so stark but its just easier to pretend to believe. And yet other atheists can even see profit in faking it. Do you really think all those TV preachers telling you to send them money are really believers? The really dangerous ones maybe, but I bet there are others who are simply con men seeing a good angle.
I know atheists who keep it hidden even in my rather liberal province of Ontario, Canada. Its a dozen times worse for atheists in the bible belt of the US. And I can't even imagine how motivated atheists must be to hide it in Islamic nations, especially if they were raised muslims.
