The absence of religion is not a religion

From time to time religious people claim that atheism is a religion too [1]. This is strange for - at least - two reasons. First of all; how can the absence of something be this very thing? How can the absence of religion be a religion? And, secondly, how come religious people take the right to define atheism from their world-view, i.e., that everybody has to have a belief?

The latter actually reflects the problem we are facing here rather well. Since a large majority of the worlds population is religious of some sort, religious people simply take the right to define the reference frame from which to judge everyone's views on their own religious believes.

This reference frame, sort of, sits in the word "atheism" itself. Atheism is defined relative to theism. Actually it should be the other way round. Let's illustrate this by trying to replace the word "atheism" with a different word, e.g., "freethinker" [2]. If we call all people that are free from religion freethinkers, than Christians, Muslims, Buddhists, Hinduists, Jews, Shintoists, etc etc etc, are afreethinkers or non-freethinkers.

Get the point? Hope so. But let's take a one more example. Ghosts. I know that many people believe in ghosts but the large majority does not [3]. Hence you would assume that someone you just met somewhere in the street does not believe in ghosts. You might, however, eventually find that this person actually does believe in ghost [4]. Now, the question is: how many people would have to believe in ghosts to swing the balance so that is you that has to come out as an "aghostic"?  

Since repetition seems to be a fruitful concept in pedagogics, lets add yet another example. Science. If I am supposed to "believe" in the Higgs particle (yes, pun intended), I reasonably ask for the evidence (see, e.g., here for the current status). Similar with so fantastic a thing as gravitational waves [5]. Now, if I tell you there is a teapot in some orbit around the sun and you do not believe me, how would you feel if I tried to define your non-believing in the existence of this teapot by calling you an ateapotist and claim that your non-belief in the teapot is as good as mine, i.e., it too is "a belief"?

Well, this is the classical burden of proof problem. In the the case of the teapot or the ghost most people will see the point. But when it comes to religion the claim that atheism is a religion too remains widespread.

But it is nevertheless false.

Notes:

[1] Religious people do, of course, their best to spread this claim which I see as nothing but cheap propaganda. Guess it helps them to reduce their cognitive dissonances and makes them feel better. A recent example from Sweden is found here. A good comment and some background on this article by Jonna Bornemark is given by Patrik Lindenfors. 
[2] I don't think this is a good word in this context and in a way the word "freethinker" contains the same problem as "atheist", but, for the sake of the argument, let's use it here.
[3] Though I might be wrong with my "large majority" believe here.
[4] And you might be fine with it as long as the person does not try to convince you and does not do you any harm based on this ghost-believing thing.  
[5] Wow, look at the list of authors at the end of this paper and compare it with the author list of some "holy" scripture ...