James, you missed his point. I believe he is trying to say that atheists say they are not religious, but some atheists act religious about their atheism. Religious, meaning behaving like fundamentalist evangelists. You can find good examples of it on this thread.
That was, I assume, addressed to JamesPenton on the basis of a comment that BTS made?
If so, I agree with BTS on this subject. In fact, I classify myself as agnostic to avoid being lumped in with this kind of atheist. Madilyn Murray O'Hair was a typical example of this "atheist evangelism".
However, I think the real majority of atheists are perfectly happy to get along with religionists so long as religion does not try to interfere with human rights or do harm to other people. They do not prosylatize, and this may be the reason that they do not necessarily try to force their kids to also be atheist.
That may be the reason for the findings of this poll.
BTW - just for the record: Are there similar "unknown" percentages in the other religious categories of this poll? I think I will go have a look...