I think we humans need such areas to in order to keep our hubris in check, and to remind us of our proper place in the scheme of things. We are a part, not apart, and certainly not above, the Earth.
I remember on solo on my Outward Bound trip (in Canyonlands), how I was struck by a paradox that occurred to me, as I was hurrying to set up my little shelter before a storm moved in. The paradox was this: the environment is at the same harsh (it can kill us), but fragile (humankind so easily destroy it); demanding of me, yet indifferent to me and my fears. I looked around at the huge, overwhelming size of the wilderness I was in, and thought, "It is so big, and I'm so little."
It was a very humbling experience.