Pet Sematary is the most disturbing novel I've ever read. The scariest part, for me, has to be when Louis grave-robbed his own son. It was absolutely disturbing and hard to forget.
As for your thinking, none of that crossed my mind, to be honest, lol. But that's some strong thinking there.
The only thing I had trouble getting into was the whole murderous little boy scenes. I found it a bit silly more than anything else. And I also didn't like the ending -- a bit too Hollywood for my taste. Still, by far one of my favorite novels.