Ok, let's go with that. What can you photograph outdoors that does not have someones efforts to style an area?

If the photo's "of" an artist's work then you probably do owe the artist. If you're photographing something that happens to have an artist's work in the background, that's going to be fair use, like the "dancing baby" video that has a bit of a Prince song in the background.

Nature?

(I suppose you could argue that the ability to get to said nature is often dependent on roads and other transit networks...)