Because there is nothing to refute; I don't know what God is. This is not an active denial of God.
My belief or disbelief is neither a confirmation nor refutation of God's existence, and neither is yours, nor anyone else's for that matter.
My objection and first observation was that your reply was not responsive to xzins' question and so I rephrased it as follows: "Or to put it another way, why would an atheist be interested in someone he denies exists?"
Why don't you ask a declared atheist?
Neither xzins nor I directly accused you of being an atheist
Certainly, xzins did not—he only stated that it seems that I don't believe either in God or pink unicorns on Jupiter, but you jumped to the conclusion that I deny that God exists by asking me "why would an atheist be interested in someone he denies exists." I never said I am an atheist and I never said that God doesn't exist, so why would you ask me unless you presumed otherwise?