Because Atheists are usually hyper-sensitive and full of themselves and it pleases me to piss them off. Now that I've gotten you guys, I'll tell you that another thing I like to post is the study about humans being wired to believe in God and another study about atheists being given a lie detector test and asked if they believe in God (and they all fail the test).
An atheist is a person who denies or disbelieves the existence of a supreme being or beings. That's huge. So it begs the question, what kind of proof would an atheist require to believe in god?
There is no proof that God exists.
There is no proof that God doesn't exist.
A belief is a trust or confidence in the existence of or truth about something without any proof.
Thus, just as a person of faith knows there is a god, one who claims to know there is no God bases that claim on a belief. As faith is a set of beliefs, atheism must also be a faith.
An agnostic is one who realizes that they have no proof either of the existence of a god, nor of the nonexistence of a god. Lacking any emotional attachment to the topic, it seems as if the most rational approach to the topic would be from the standpoint of an agnostic.
It is strange that people see the statement that there is no proof that God exists and jump to the conclusion that there is no evidence that God exists. Evidence and proof are not the same thing.
There is evidence both for and against the existence of God, and rational people make judgements based on the evidence after they examine it. Irrational people prefer to make judgements based on not examining the evidence, and then assert that they are more rational because they reject the evidence because it does not amount to proof. There are people that believe in God because they are irrational, and there are people that are atheists because they are irrational. Both of these groups reject evidence that does not fit their worldviews, and neither side is capable of listening to reason.
There is no proof that dark matter and dark energy exist. Scientist look around and see that if all they see is all that exists then the universe cannot exist as it is. This is evidence that something exists, and they go about looking for more evidence of what that something is. They rationally examine the evidence, and reach conclusions based on that evidence. That evidence mostly consists of proof that the other possible explanations are wrong.
The evidence that convinces rational people about God is often subjective, and sometimes comes down to proof that alternative explanations are not possible. Faith is not believing in God without evidence, it is examining the evidence and accepting that it points to something we cannot prove. Not only do I have faith in God, I have faith in science that tells me that other things I cannot see exist. Do not reject God simply because there is no proof He exists.