How does religion work in Fantasy settings?

Here’s the provocative opening statement: I don’t believe any major fantasy work tackles religion, even (perhaps especially) fantasy novels or RPGs that involve actual Gods. (I may be wrong about Runequest, but I don’t think so.)

Consider.

The Lord of the Rings does not involve religion at all (disregarding any allegories I may have missed - Tolkien and C S Lewis were drinking buddies, after all). Hobbits, elves, dwarves, orcs and both types of men (Rohan and Gondor) are alike in not having anything like an established religion. There are no subterranean elf- or Gandalf-worshipping cults, or for that matter treacherous freemason-like Sauron cults in Minas Tirith.

AD&D does not deal with religion. Yes, there’s a cleric class, and there are gods that give powers to their followers, but that doesn’t mean that AD&D religions are religions the way we would understand them. There’s no faith required to follow a religion in AD&D - you know the God exists, hell, you know a number of gods exist, it’s just a matter of choosing which one. Religions are more like political parties than anything else - you mostly belong to one because of your background or upbringing, and for the elite few it might get you material rewards, you tend to follow a particular religion because of personal inclination but that doesn’t mean you have to believe to reap the benefits.

Following a particular god and applying his code of morals or behaviour does not make you religious. If it did, then judging by its code of conduct, Disney Corp. could qualify as a religion (with all the tax breaks that accompany such a move). I shudder just at the thought - so, Cyberpunk GMs, you know what to do ;-).

It also doesn’t follow that because you live in a fantasy world you should follow a particular religion. See for example Terry Pratchett’s Discworld. There’s weird stuff going on all about them, but they’re used to it so they don’t think it’s weird. Religion, it seems to me, is all about uncertainty, doubt, hope and fear.

That was a very broad brush approach, and I’m sure there’s a lot wrong with it - my religious education was scanty, to say the least. If anyone can point me towards a decent history/treatise of religion, then please do. I’ll be very grateful. I’ve read the first part of the Golden Bough and found it heavy-going; any alternative recommendations will be well-received.