The existence of a god does not require the existence of a religion.
Also, many of the 'kill all...' statements you introduced are extrapolations made by fools as opposed to the actual religious doctrine as any sane person would see it.
That said, I don't like organized religion, because it does cause a lot of death, and results in a marked superiority complex which I find disgusting, especially within my own people.
However, the existence of God DOES require evidence and proof. Otherwise, why don't people believe in unicorns, Santa Claus, tooth fairy and zombies- because there is no scientific evidence.
have you ever tried to establish the exitstence of a god for yourself using rational logic?
Some people believe in god because it makes sense to them, and because they don't have the arrogance and/or creativity to try to understand everything.
Others believe in God because they have the arrogance to want to say that their way is THE way.
Others (like me) use the idea of a Godhead as a method of furthering their own understanding, belief or not.
Either way, the fact that you're acknowledging the idea of such a being means that it must exist in some form, perhaps within the consciousness with which you view the world.
Have you considered that all existence could be circular and actually depend on the consensus perception of humanity. As in, I perceive the existence of a god. Therefor, within my perception, god exists. God is the creator and causes me to be. But it is my consciousness that spawns the idea of god...
etc
