The more something matters to someone, the more we can expect the person will resort to specious arguments to defend it, because it's really certain emotions that are doing the work. This is certainly true for religions, and although it's not likely true for atheism itself, there are atheistic emotions that arise to protect science, progress, human freedom, and so on. I suppose a pure skeptic would have to be like a Star Trek Vulcan, aware of everyone's weaknesses, including theirs.