"The irony is that the AFA is acting like a religious organisation.
Billboards trying to encourage people to not put down a religion?
What's the difference between trying to convince someone to have a religious belief and trying to convince them to not have a religious belief?
Its fine to be an Atheist just don't call yourself an Atheist if your trying convert people to your beliefs.
This is what religions do."
Totally wrong. They are saying put down no religion if you aren't religious, they aren't trying to blackmail you by saying you will go to hell if you don't believe. Did you read the billboard message? It says "Not religious now? Mark 'No religion' and take religion out of politics", not once on that billboard does it try to convince you god does or doesn't exists, just to state the truth. In America this is much more common, atheists will say they are religious to avoid being ostracized.