There is a superiority complex that comes with it that I don't expect Chronic or most atheists to admit. Hey, when I meet a very religious person, my superiority complex starts blinking.
What you're doing there is begging the question. You're implying that you're right about this and atheists know it but just won't admit it. Nein. They won't admit it because they disagree, so nothing to "admit." Superior is the wrong word. It's a word those who disagree with atheists use because it automatically sounds wrong. The feeling is simply that one is more thoughtful, informed, perhaps intelligent, and unconditioned than believers. If one is correct about that is it a psychological complex to know it or just one more sign of its truth?
Atheism may not be an ideology but there is a common set of beliefs (a belief not being faith-related, but simply a conviction and confidence in an assertion about the world) associated with atheism. That set might consist of rejecting religion, believing in evolution, etc. In other words, if you were to question all atheists in the world about certain views, there would probably be about 2-3 same ones that would echo.
If many atheists share a lot of the same convictions it's because rationality and informed intelligence will usually get to the same truths about things. Just like mathematicians will usually agree about the answer to an equation. Not because of group think. Of course, it's not as exact as mathematics, but you get my point. Truth is truth. And those best equipped to discern it will discern alike, up to the limits of what is presently known.
Also, a lot of atheists share the same convictions because religious believers have set the agenda for us by arguing against certain things or for certain things that go against rational understanding. And since atheists like to be informed, they follow the atheist/religious debate and know what the hot topics are and have an opinion, which is usually the same because obvious truth is obvious to similarly informed rational minds. Same thing with vegetarianism.
Atheists like to point out that atheism is absence of belief. But there's the faith-based belief and belief, as I stated, that you have a conviction about something. You have a conviction that God, in the Abrahamic sense, does not exist. In other words, you have a belief.
So what's the point of using the same word when it means something different from how atheists use it? Like you're saying, ah-ha gotcha! "You eat veggie burgers, therefore, you do eat burgers!" "You Believe that two and two equal four. In other words, you have a belief." What's important is how did one come to that belief, conviction, or understanding, not the word used. Did you come to it by evidence or some other way? Atheists usually don't accept that other way.
An atheist does not believe in God, which is not a belief. It's a disbelief, an anti-conviction. And it's not the same as the conviction that there is no God. That's anti-theism, not atheism. Lack of belief cannot be a belief. Just like silence is not a sound. Just like not collecting coins is not a hobby. (And I don't have quite a collection. You'd have to not see it to believe it, something that comes easily to the religious.)