If my claim that creationists don't believe in creationism, why does anyone even claim to believe in creationism?
There are three reasons.
First, many people are ignorant of what evolution is. A surprisingly high percentage of the general population believes that evolution is about things like monkeys giving birth to humans centuries ago without any intermediates. That’s not evolution. These people can be helped by doing a better job of teaching evolution in our schools.
Second, many creationists consider evolution to be, quite simply, an evil idea. For them, even if it is valid science, telling everyone about it would do nothing less than destroy society!
Here’s what one creationist web site says about this:
“The teaching of evolution is evil, it is a deliberate attempt to shake the faith of young people in a Living and Holy God. Teaching young people that they are animals (mammals) is evil. The Bible teaches that we are not animals, we are human beings (1st Corinthians 15:39). Deliberately educating young people without including God is evil.”
Of course, the idea of God is not inconsistent with evolution. It is only inconsistent with some interpretations of the Bible. For example, if the Earth is but a few thousand years old, then the evolution of all life on Earth from a common ancestor is impossible. But this argument only works if someone’s interpretation of the Bible is inerrant and the Bible itself is the inerrant word of God. Otherwise there are no conflicts.
As I have said elsewhere, even if evolution is evil that doesn’t make it untrue. Adolf Hitler was the epitome of evil. It would be silly to deny his existence because of that.
Some people who use this argument actually accept evolution. They just don’t want it to be taught in schools because they feel that it will cause morality to decay. A good way to answer such critics is by pointing out that evolution through “natural selection” is little different in concept to the free enterprise system. Evolution is no more evil than is capitalism.
The third reason that people are creationists that they believe very strongly in Pascal’s Wager. This might be the most popular reason. In their view, a professed belief in an inerrant Bible might get them into heaven whereas they lose nothing if that belief is not true.
The argument that I make to counter that: close scrutiny shows that creationism demands a belief in a God who is cruel, deceptive and not very competent. Such beliefs are hardly the way to buy one's way into Heaven.
 http://www.jesus-is-savior.com/Family/public_schools_are_evil.htm, referenced on December 31, 2008