So you can't tell the difference between how David Foster Wallace, William Langeweische, and Steven Levitt see the world by reading what they write? Or the difference between a conservative-leaning historian and a liberal historian? Come on.
You realize that DFW was primarily a fiction writer, yes? Sure we all like A Supposedly Fun Thing I'd Never Do Again, but Infinite Jest was his Magnum Opus, and was fiction.
Without getting into the Latrodectus Mactans Productions quiz to prove our geek/hipster DFW cred: I just picked three writers of nonfiction with both very different prose styles and very different worldviews, and I don't think you'd disagree with my point.