Because the biblical citations are part of a book that essentially says,"God is the one true god, and everything in this book is true because it says so in this book." It can't change. That story remains the same no matter what is discovered, whereas theories like evolution are subject to change as more evidence is found, and if enough evidence is found to support the contrary, the theory would be thrown out the window. It isn't about unfair, it is about evidence (that is more than just a book proclaiming itself to be true) to back up a claim