overthehill - I actually think there is a lot to be said for the basic love-thy-neighbour teachings of Jesus Christ. I don't disbelieve in him as a historical figure, although I'd doubt the veracity of a lot of the Biblical claims. I just don't think that his teachings were in any way divinely inspired, nor that there is such a thing as the "divine". (As a sidenote, it's dispiriting and shocking to read some of the examples of "YOU ARE GONNA BURN IN HELL, SUCKER"-type correspondence which Richard Dawkins gets sent to him - and makes public - from people claiming to be Christians but obviously having no empathy at all with the idea of Christian charity...)
And I'm glad we agree a caring ethos is by no means exclusive to faith schools.
I think the answer to your last question is - there probably aren't that many which entirely exclude non-believers. (I know a couple, but they are very small. )
The point, I think, is that they are state schools which have particular entrance requirements, the biggest of which is that they strongly prefer you to have an affiliation with religion, and to demonstrate this in a convincing way. Even if most faith schools now let in a token 10% or whatever it is of the children of non-faith people (I'm happy to be corrected on the actual figure), it's still vastly skewed in their favour. My issue with it is, and always has been, that religion is at best of debatable use and at worst an irrelevancy, and that it should have no place in a state school system.
To be clear, I'm not arguing that, if a faith school exists, it should let in anyone and everyone. I'm arguing that it shouldn't exist as a faith school in the first place. (NOT, as some seem to wish this to mean, that the school should close - merely that, if it's a state primary or comp, it should be a school with the same entrance criteria as all others in the borough and the same curriculum.)