I feel unbelievers are not being reasonable, logical, or rational here. The concept of things like angels, demons, God, souls, aliens, ghosts, etc. merely sound strange and bizarre to them. They have an emotional reaction to these claims, but there is no logical reason to treat these claims with more skepticism than other claims.
I have argued this dozens of times before, yet not once has an atheist presented a logical argument for why these claims should be treated differently. I have only heard them claim it's simply common sense, yet no matter how hard you press them, they won't spit out a legitimate logical argument.
So, we have established that this is a physiological issue, not a logical one. So, why is it that unbelievers have an aversion to these claims? To answer this question, I looked for common trends among the claims that seem to provoke this reaction from unbelievers. The only common trend I could find is a non-human intelligent mind.
For example, God is viewed as a spooky, supernatural explanation for the origin of the universe, where as a multiverse model is viewed as scientific and reasonable. The difference here is the fact that God is a mind. The idea that there are minds beyond humans is scary, and this is why unbelievers fear "supernatural" claims.
Really, it doesn't matter if it’s God or not. If you pose an explanation for a phenomenon that involves a mindless process and an alternate explanation that involves a non-human intelligent mind, most unbelievers (and even some believers) will overwhelmingly prefer the mindless explanation.
But again, there is no logical reason why a non-human intelligent mind is a less likely explanation than any other. My only explanation for this is that unbelievers fear the idea of an intelligent non-human mind because it is something they can't possibly hope to understand (as even a human mind cannot be fully understood), and as most know, people fear what they cannot understand. This is a purely emotional phenomenon and nothing more.