But what you're saying with THAT is "people have the capacity for abstract thought, therefore God". It's a non-sequitur.
No, it isn't. What I'm talking about is belief in a higher power. I don't see how or why it would have evolved naturally.
There's this thing called death. It kind of sucks, and nobody really knows what goes on with the individual after experiencing it. We just know that once someone dies, they don't talk to us anymore, and that makes us sad. We also don't know if we have any degree of consciousness after death, which terrifies us. So, people being afraid the natural phenomenon create a supernatural phenomenon to assuage these feelings of melancholy and fear.
Once this idea comes into play, it really isn't too difficult to transfer it to a god. My neighbor is an asshole who beats his wife and kicks puppies, and yet he's rich. There must be something beyond the scope of our existence that can give him some comeuppance. So, the idea of god as this omniscient judge that holds everyone accountable for evil acts soon follows.
I'm not saying this is exactly how it developed, but I disagree with the notion that we are hardwired to believe in concepts of gods or after-lifes. I find it far more plausible that early peoples, guided by ignorance of earthly phenomenon (like lightning and earthquakes), guided by fears of dying, sadness over loved-ones, and just-desserts created early concepts of gods and after-lifes. From there, subsequent generations were indoctrinated to the point that it appears to be "hard-wired."
ETA: The practical point of this post being that your logic rests on a few assumptions. First, that people are, in fact, predisposed toward supernatural beliefs. Second, that this belief could only come from god, as opposed to temporal sources. If these two points are assumed, your logic holds up quite well. However, I just provided an alternative explanation that leads to the same result and requires neither assumption. Ergo, your logic rests on faulty assumptions and is inherently flawed.