I think it is why people like me who call for proof of the claims made by their former religions are seen as mean-spirited, hostile, bigots or crazy.
We've broken the rules of polite social engagement.
A recent article in the New Yorker detailing Paul Haggis's apostasy from Scientology is a great object lesson in what transpires between people when the metaphors that make up belief are questioned for their reality.
The apostate's sanity or honesty are called into question despite the objective evidence one has to justifiably infer a religion's theology is bunk.
For example, I've come to see that a post-enlightened world of common descent, quantum mechanics, and the double-helix of our DNA does not afford much space for the interventionist god of abrahamic theism or the unmoved mover of classical theism. I therefore think it is silly to call myself Christian or Spiritual in any substantive way.
The metaphors that make up the definition of Yahweh, Jesus or spirits are unconvincing in the discoveries science has provided.
I don't think many modern believers if challenged would argue for supernaturalism when faced with naturalism's victories either.
Of course there are the Pat Robertson followers who will seek to understand god's "to do" list by analyzing natural disasters (e.g. The Haitian earthquakes as god's vendetta against Voo Doo or the snow-storms hammering the US East Coast as god's retribution against the gays) but the pre-enlightened "experimental religion" of Jonathan Edwards is resigned to the cultural scrap-heap of faith-healers and Tarot card readers.
I doubt anyone who has built their career on the observation of Christ-centered teleology will be named President of Princeton, as Edwards was, anytime soon.
Most modern believers see a god concept as a form of self-help to navigate a world that involves modern institutions (evidenced most notably in the work of Rick Warren).
These modern institutions rely on both methodological and metaphysical naturalism for their invention (e.g. the germ theory of disease as a basis for inoculation rather than spirits as a source of affliction) and therefore avoid supernaturalism as a cause.
The supernaturalism for most functioning believers in a modern world has regressed to a personal philosophy that allows emotional spikes to be framed by terms that offer a short-hand method for admitting them or justifying them.
For example, in my former experience as a Calvinist Christian, sin was a reality evidenced by the lack of perfection I experienced in either my thinking or behavior which in turn motivated a theological practice towards better behavior. I couldn't however point to a generator of sin because it was a function of my soul and therefore a product of a non-investigatable entity. Thus sin operated more as metaphor in explaining the basic reality of what I've come to see as biological and brain functions rather than being basic unto itself.
The result of metaphors like sin become theology and theology offers easy access to a social group and belonging based on the shared belief that the metaphor is basic. I don't begrudge this. It feels good to count on a society that will agree with you and always love you.
It does suggest however that a belief in unseen agents (e.g. "God" or "gods") is a function of emotional experience rather than testable ideas and therefore it seems to be more about wishful thinking to navigate one's inner life rather than understanding what makes up our shared external world.
I also think it is why when one admits apostasy towards a given religious tradition it often invites both aggressive and passive hostility from the people with whom the apostate once shared religious belief.
A person who sees theology as metaphor, and admits its usefulness is in providing comfort for those believing in the symbols of that theology, seems to be behaving like a bully telling another their organizing ideas of reality are of no deeper substance than "Goodnight Moon".
I of course believe that all theologies are of the same essential substance as fairy-tales, and don't mind believers who wish to admit this, but also find the need to justify these stories in ritual as ineffective to any real moral or intellectual aims.
The difficulty however is that believers who will dismiss the efficacy of their theology when faced with real circumstances modernity has tackled (e.g. antibiotics as first-line therapy for Streptococcus rather than the laying of hands by elders and the anointment of oil) will not admit the subordinate nature of their metaphor when considering reality.
They insist that their metaphor is real.
I've offended many people in my short time as an atheist because I've challenged the assertions they feel to be real as real in any meaningful way outside of their feelings. I once was concerned that I needed to apologize for this unintended offense but now see it as the inherent danger of apostasy. Now that I admit the function of religion as a natural phenomenon I can understand why I make so many of my former friends uncomfortable and, while sad for the friendships I seem to have lost, I no longer worry about what I could have done to change the outcome.