Why telling atheists the truth is like telling someone that smoking is harmful and they still smoke?

Why is telling atheists about God existence being real is like showing the warning label on the back of cigarettes to smokers, that it can do harm to their body, but they say "yea I know," and they still continue to smoke dispite the harmful affects that can be done? Just like God, no matter how much you show them why God exist (think of the warning label showing the harmful afffects that can be done to smokers, and they still ignore it), but they still aren't willing to accept your proofs becuase, not out of blindness, but rather a sense of arrogants and naiveness on there part. Maybe, some people just are unwilling or jealous of God for no apparently reason--might be that Satan allows them to be that way, so he can get as many people as possible to take to Hell with him.