Children don't feel excluded and angry if they're not labelled by the political leanings or musical interests or sporting affiliation or whatever other personal belief/interest of their parents.
I agree with the sentiment behind this but would like to throw another idea into the pot. What you say about musical interests and politics is very true, in some families but whether it's true in families where those leanings are seen as the central and defining quality of the group I'm less sure. Look at Tony Benn's family, his offspring have followed suit into politics 2 out of the surviving 3 being elected and now his granddaughter also joins the fray. I remember a conversation with my horse boss over when to buy his daughter her first pony, he was in no hurry to rush things but by the age of five he was beginning to think about her starting to ride. I was very pro her having a pony, not because I think 5yr old's in general should have their own pony but because HER entire family and social group rode, because horses were the primary topic of conversations, because what was learned in the yard defined the way of being as people - 5yrs old is old enough to join your tribe and begin to learn what it is that binds them. It worked out rather well I might add.
For families that fall into the non practising groups with regard to religion I would totally agree that it is in every way level to interests and politics but for those in families who define themselves first and foremost in terms of religious belonging I don't believe there is any parity to other interests.
For children who grow up defined by religion there are many challenges, I don't doubt that for a second and those need to be addressed. I'm not in favour of no action, just action that has as it's goal a plausible effect. Introducing critical thinking into the national curriculum (here in the uk) would mean it would have to be evidenced even with those pupils home schooled, more to the point it would have to be taught in all schools. Forceful indoctrination usually involves isolating people from alternative ideas, this isn't just for fun it reflects the incredible power of alternatives to disrupt brainwashing attempts.
I would rather tackle a parent's ability to isolate a child from ideas than worry over how they describe or the kid describes themself . I do think state supported faith schools is an issue which should definitely be campaigned over in a way that maintains the value of faith schools who educate kids well - ie just closing schools would be a bit dumb where the alternatives have more problems of a different nature than the school being closed.
"Whatever it is, it spits and it goes 'WAAARGHHHHHHHH' - that's probably enough to suggest you shouldn't argue with it." Mousy.