Slightly off topic, but...
Unless I'm mistaken, I'm fairly sure that you (in the scheme of christianity) cannot be damned for ignorance. Which is how they explained the whole 'majority of the world population is not christian' thing. So basically, by being a missionary and teaching people The Way, you are actually condemning most of them to an eternity of unimaginable torment. Same thing if you teach your own children about your religion. Funny stuff.
If people stopped handing it down to their kids and just made it available as an option, I'm fairly certain that most religion would die out in one generation. And no, it would not contribute to any major moral decay.