To all non-believers...?

Do you not believe due to a lack of physical evidence OR some other reason? I an an atheist not because there is no proof of God, but simply because it is not likely that these stories are true. The bible stories are based upon pagan stories written before them, there are literally thousands of "gods" throughout Earth's history and the universe is so enormous, the sheer size is beyond our comprehension. It just isn't likely, that the God described by certain inhabitants of earth at this particular moment, is correct and the gods of the ancient romans, greeks, mayans, native americans etc.. are wrong. Not to mention the unknown peoples possibly living (or have lived) on other planets.