There are two types of irreligious people IMO:
1) People that weren't brought up with religion and don't give it a second thought except for when a muslim blows himself up or when a priest is caught buggering a kid.
2) People that were raised in a religious home, rejected it at some point in their life and now spend all their time fighting against it.
That's it, is it? You reject religion and you spend all your time fighting it?
That makes up for a lot of time and who exactly would these people be fighting against and how?
No scope for critical thinking people looking into something that had been thrust upon them, in order to make up their own minds? None?
How many free thinking people that weren't born into religion, have found that there is a God and that he deserves to be worshipped?
How many free thinking people born into religion have found out that the God they've been weened on doesn't actually exist?
That would make for an interesting study through the Western world.
Back to the OP: On what basis does this 'irreligion' become a religion? If it did though, I wouldn't want any part of it.