All writers put their worldview into their works. They don't do it intentionally or deliberately - it's an unavoidable consequence of being human. As a reader, you can't avoid it unless you want to stop reading.
There are a lot of things in Mistborn that resonate positively with me, as a Mormon. I can clearly see the influence of the LDS perspective; it's one I share, and I like that. Elantris - actually, it was the Mormon view on courtship, family, and love that came through strongest in that one for me.
As a counterexample, I've read a few books by Holly Lisle. They're great stories, and I have nothing against her skill as a writer. However, she has very strong liberal and libertarian political views and a vehement anti-religious bent, and it shows in her writing. I don't hold it against her; it is, as I said above, not only natural, but inevitable. Nevertheless, it lessened my enjoyment of the books enough for me to stop reading.
Can you enjoy an author's work whose worldviews you don't agree with? That's the question you've got to ask yourself. In my case, it depends on the author, and on the views.
Now, let me ask you something.
I'm interested in how others feel about how Sanderson's faith has influenced his novels, with examples given from his writing, and also any portions of his novels that reveal a break with Mormon teachings. If I'd been aware of Sanderson's beliefs at the time I'd read his books, I'd have had a keen eye on which characters if any imbibed coffee or smoked tobacco.
Why do you care about things that reveal a break with Mormon teachings? Are you looking for fuel to call the author a hypocrite? Or are you just trying to feel better about reading a book written by a Mormon?
I don't remember any mention of either coffee or tobacco in any of Sanderson's works. As far as I can tell, they don't exist in his fantasy worlds. Tea exists in Mistborn, and is drunk by characters both good and bad. Same with alcohol. What does this say about Sanderson, or his books?
Actually, not a whole lot. So he portrays characters doing things he would not himself do. News flash: that's what authors of fiction do. Again, I'm not sure why you even care.