Why do Atheists spend so much time debatng the existence of God?

[Simsim]

You mean like following his commandment about "thou shalt not kill" while being a front line soldier in the Army, "thou shalt not steal" as they embezzle money from the bank they work in, or ignore the poor & homeless and hoard massive wealth after Jesus said not to?

If people kill or steal that is because they are bad not because they don't follow God's commandments. If they don't that's because they are good not because they follow God's commandments. If they do other strange stuff like wasting time in pointless actions or preventing themselves from making love that's because they follow God's commandments not because they are good or bad.