I do not differentiate between agnostic and atheistic thought. They are both the same thinking/belief systems in my view. An agnostic believes there could be a "god/creator" (but does not pursue this thought any further than "maybe"). An agnostic also believes there may not be a God/Creator given the absence of evidence to justify such a belief. An atheist believes that there is NO god/creator given the absence of evidence to prove the existence of such a being. If evidence had to exist then the atheist will believe the existence of such a being based on such evidence. That sounds exactly the same.
As to your point about "we don't know" - well, not knowing is perfectly fine in science. We cannot ascribe to or embellish and fabricate imagined facts and agents to any unknown phenomenon without evidence.