1. The reason that people argue about evolution/adaptation is because of the data that shows changes in populations over the course of thousands of years. People argue against the data that shows the evolution of a species. If the data showed no changes, then no one would be arguing evolution because there would be no evolution/adaptation to argue about.
2. No one has ever argued with someone over the contents of a book that did not exist.
I would guess that someone has argued of the contents of a book that did not exist at some point. There has probably been an author who died, and there were rumors that an unpublished book existed; fans of the author may then have argued over what the book would be about, or what would occur in it, even though that book may not have actually been more than rumor.
I'm not sure how this relates to god. The concept of a god clearly exists, so some argue for it or against it; were you trying to say that if the idea of god didn't exist, no one would be arguing about it?
People argue over things that they feel strongly about. Do you know of any other concept that people don't believe exists that they feel strongly about?
Ghosts. A soul. An afterlife. Reincarnation. Intelligent life other than humans. The Holocaust. A better mousetrap.
It seems you have switched from arguing about the concept of something to actually arguing about the something. Does that mean people argue against the existence of God instead of the concept of God?
Let's put that aside though, I have to disagree with you. Ghosts, A soul, An afterlife, Reincarnation, Intelligent life other than humans, The Holocaust or A better mousetrap do not come close to matching the magnitude and degree of opposition that belief in God evokes. It has no contemporary comparison. Just look at the disrespect.
There is no ‘disrespect’ in acknowledging the fact that there is no ‘god’ as perceived by theists, it’s simply acknowledging the fact that there is no ‘god’ as perceived by theists.
And it isn’t ‘opposition’ to a belief in an omnipotent deity, it’s an opposition to the consequence of such belief: the arrogance, the ignorance, the hate, bigotry, and racism that manifest among far too many theists.
We see examples of that hate and bigotry in America daily, as theists seek to violate the rights and protected liberties of gay and transgender Americans, and discriminate against gay and transgender Americans in places of business.
Of course most theists do not harbor such bigotry and hate, and many speak out against it; indeed, the majority of gay and transgender Americans are persons of faith, illustrating the confused inconsistency of religious dogma, and the fact that religion and ‘god’ are indeed creations of man.