If I am a boss looking for someone to do some manual tasks, I would not mind how s/he thinks, what and what not s/he believes in as long as s/he is physically capable of doing the tasks.
If I am a boss looking for someone to do some tasks which involve logic, evidence-based reasoning, I do not care if the applicant is physically disabled as long as s/he is capable of thinking logically based on evidence. A religious applicant automatically disqualified him/herself by believing in an imaginary friend who looks after everything.
If I am a voter and there are candidates who want to be leaders making many decision for me, a candidate publicly announces his/her religion affiliation has just disqualified to get my vote. If s/he truly believes in an imaginary friend in the sky, s/he is mentally not capable of leading the country. If s/he does not truly believes in god, but pronounces that s/he is to "buy" vote from the religious, then s/he is not honest and I cannot trust his/her ability to make decision unbiased.