They're not doing it with disregard for your actual beliefs, they are doing it because of your beliefs. You have said, in this very thread, "I do not believe God exists." That makes you an atheist, by the definition of the word.
You can say that you're seven feet tall if you want, but don't be surprised if someone corrects you and tells you that you are not.
But the problem here is that many seem to be defining atheist very differently than is commonly accepted. It seems to defined here as "non-theist".
It is pretty clear Apology is an atheist by that definition. He's a non-theist, so THAT definition makes him an atheist.
However, as far as I can tell, the generally accepted definition is: "One who actively disbelieves in the existence of god" or "One who denies that god exists"
By that definition, Apology is obviously NOT an atheist.
IMHO, the statments "I do not believe in God" and "I believe that God does not exist" are NOT equivalent. One is an active belief, whereas the other is the denial of a belief. There seems to be a logical issue in that people are insisting that if I don't believe X then I must believe ~X.
The problem is, I can just withhold belief on either.
Take the question "Do you believe I am bald?" i.e. Hairism.
You can be a Hairist (believe I have hair). Yoiu can be an Ahairist (believe I DON'T have hair), or you can withhold judgement (believe neither pending further evidence).
Apology seems to fall into the latter camp (regarding god, not regarding hair

). I think his hair stance is up for debate...but by the definitions around here, that makes me an Aapologyhairist.