Rather have an all powerful God allowing pain and suffering for some purpose that cannot be readilly understood, atheists would rather experience senseless, meaningless and purposeless suffering.
Why do they do this? One of the reasons is that if we can understand a thing and can define it, then we believe at some level that we are that thing's master. We cannot understand or define life; we cannot understand or define God; consequently we are master of neither. Logic and reason are always on the hunt for definition, and anything that cannot be defined is apt to be defied. Atheism defies God and defies life. Atheism will not have anything that cannot be defined on a rational basis. They forget that the things that make up elemental human life cannot be defined.