Well you believe in the absence of Zeus, don't you? Then why doesn't that make you an atheist? (Hint: it does, since you're atheistic about a hell of a lot more Gods than any you might choose to believe in. So you're at least 99.99% atheist, or 100% atheist as the number of Gods goes to infinity.)

You believe your argument don't you? But how can you, when there is such an infinity of arguments you don't believe in?

This is word chopping, not an interesting philosophical argument. Truth is exclusionary, and the space of excluded hypotheses is at a minimum exponentially larger than the non-excluded ones, if not super-exponentially, if not some variety of simply infinitely larger, depending on how you count. Appealing to the size of the universe of false statements and/or "things you don't believe" is not meaningful.

No? Atheist literally is A-Theist, similar to amoral being A-Moral ("a" being a common prefix for "anti" or "opposite"). A-Theist means one does not believe Theism, the "belief in the existence of a supreme being or deities."

In which case, by believing in one specific God, one is not an atheist in any sense toward other religions. Believing in one specific God literally means that you do have "belief in the existence of a supreme being or deities," your only dispute is to which one.

Note that a- is a different prefix than anti-. a- means "without", whereas anti- means "the opposite of". So, being a-theistic means that you are "without god(s)". Being anti-theistic would meant that you oppose god(s). An amoral thing is a thing to which morality doesn't apply (for example, weather phenomena are amoral). Anti-moral would mean something that is opposed to morality, which would probably make it immoral (such as a human killing another human that hasn't wronged them in any way).

> imagine unbelievers tend to receive confirmation of the absence of God

Another interesting question to ponder though: Who's fault is this? Is it God for not jumping out of the shadows screaming "I am he, worship me!"? Or is it an unbeliever who makes assumptions about how a God would act, and finds there is no God because he doesn't fit the unbeliever's assumptions? In which case, what is the unbeliever but a God himself?

I remember my first joint.