OK, suppose the God character actually exists. Why would that mean that everyone has a "soul"? Maybe only certain people have "souls" and the others are simply experiment subjects to see how the people with "souls" react when the experiments are made to suffer misfortunes. So if you, who have a "soul", don't do anything to make the world a better place then you might be condemned to the lake of fire.
Or suppose there's no God character of any kind. We, as humans, are it and we can do anything we want to do without suffering any consequences after we croak. If our neighbors throw us into prison or execute us for our bad behaviors that's the sum total of our punishment. In such a situation would it really matter how much evil we do? After all, we are basically predatory animals doing what we have always done since we got our chins.
Or suppose there's no God character of any kind. We, as humans, are it and we can do anything we want to do without suffering any consequences after we croak. If our neighbors throw us into prison or execute us for our bad behaviors that's the sum total of our punishment. In such a situation would it really matter how much evil we do? After all, we are basically predatory animals doing what we have always done since we got our chins.