I certainly don't claim to know the answer to that question. But there is a point... there has to be. Non-belief takes as much a leap of faith as belief does, and I'm not arrogant (or brave?) enough to make either claim. But I know, regardless of the answer, each of us has a responsibility to ourselves and to the society in which we live to behave a certain way. To make certain choices. To distinguish between right and wrong.
I think it's a little harder, though, to figure things out.