I would say that most are skeptical because they experience a disconnect from something that has been taught as reality only to grow to accept the reality that truly is, and reality itself is free of dieties, therefore, they can no longer believe that others really do have a connection to reality when a deity is thrown in the mix.
So when an explanation is desired, and reality or at least something that shows hints of reality cannot be provided...then no, reality won't work that way. Crazy does-For lack of a politically correct word.
Yes, they experience a disconnect. You are right in that they have been taught something about deity and found out that that teaching did not compute with their personal consciousness....It didn't
feel real because your "vibration" is different and you need to search for your own connection to "God". The word "god" throws too many people off track because they are still thinking like they were
taught as kids to think. Toss that out the window and find your own connection. Most unbelievers, however, don't have the spiritual energy anymore to do it. It has atrophied and they are perfectly
content living their lives without it. It's their choice. It doesn't make them a bad person.
If it makes you feel good to call believers "crazy", then that's your thing. There are crazy people that are believers and crazy people that are unbelievers. Crazy can cover a broad spectrum of people.
Where do you think the term "mad scientist" came from? People thought their "knowledge" was idiocy, but later....sometimes centuries later, they were proven correct. Crazy is not in the knowing or not
knowing.....it's all relative.