Without the threat of punishment or the promise of Paradise which comes with God, why are we even here? Why do we even exist? Because some molecules smashed together?
This really boils down to one’s sense of aesthetics. To you, clearly, the notion of the universe being capable of producing and sustaining life capable of asking such questions isn’t enough. For others, the idea that we were shaped by natural forces is, if not satisfying on an emotional level, remains so on an intellectual level. For myself (I won’t speak for anyone else), the notion that natural forces and, for lack of a better word, a long series of accidents and steps, makes life very precious indeed. Perhaps it’s only happened once in the last 13.75 billion years.
I fail to see why the value of life is any greater or any lesser because one believes in God or one doesn’t. After all, there have been those who have believed in a Creator who have, on occasion, espoused what I view as a rather nihilistic view of “shoot them all, and let God sort it out.” So you see, even those who believe in God can lean towards a pretty frightening kind of philosophical nihilism.
What I do find is that atheism seems to make some theists uncomfortable. In part, I suspect, it’s because it appears to be such an alien view that they can’t make heads or tails of it. Another explanation is that some people truly believe that the only thing that prevents anarchy is a belief in God. Without it, the view seems to be, we would see ourselves, or at least fellow members of our species, as without value or purpose, and thus abusing or murdering them is of no particular consequence.
I’m a bit of a utilitarian. History is replete with examples of where belief in gods hasn’t restrained violence, and has in some cases been used as a justification. I’m not blaming religion, other than that it becomes another tribal marker; a way to separate “us” from “them”. I also believe religion can be an extraordinary force for good, and in general, particularly with religions like Christianity and some strains of Buddhism, there’s a sort of egalitarianism at the core of the beliefs. But there’s also a danger, in my view, in concentrating far too much on the afterlife, it leads to a sort of “temporal nihilism”, where suffering on Earth is seen as acceptable, if not ultimately beneficial, because, after all, we’ll get our reward in the afterlife.