Moving The Goal Posts

I once heard Michael Shermer remark that there are remarkable similarities between the various religions, and somehow this shows that all religions are simply the outplaying of some aspect of human nature. I find this strange. In every other endeavor inter-subjective agreement is considered a sign of reaching out to real truth. But in religion, it is a sign of just the opposite. Shermer is simply moving the goal posts. If all religions were radically different he'd be using THAT as evidence of the subjectivity of religious truth.