Vinphetamin,
I like your reasoning and agree with your conclusion, but the implied question "Why DO humans do the god thing" is I think based on a few simple principles that you can observe for yourself.
Humans are not dinosaurs, or any other animal and assume, because they can think and talk &ct., they must be "special". They exhibit the same territorial and tribal dominance behaviour as other animals, but with much more destructive weapons. Their feeling of "specialness" makes them think that they were "created" in a different way, and have a wholly different destiny than the rest of the natural world. This, of course is a self-delusional confidence trick.
It is part of the human psyche to believe that things are just about to get better. In many ways this phenomenon is good as it helps us get along without too much despair, but when religion enters the equation it is used to "confirm" those thoughts of a wonderful God eventually taking us to a glorious yet indefinable never-never land.
Finally, religion has been used since prehistoric times as a means of social control. The rulers use religion and the guilt response to keep the population in tune with the thoughts of the earthly leaders. For example, the idea that Roman Catholics commit a sin by using contraception (denying natural life; killing unborn people; guilt, guilt ,guilt!) is in fact a mechanism to create more Roman Catholics and dominate the world.
Religion is a vast confidence trick, but do not belittle those that practice it. It is only the behaviour that is crazy and ultimately futile, the people themselves are usually as nice and/or as nasty as anyone else, and just as valuable.
Stay safe and live long.