Living in an area with earthquakes and volcanos, I think I understand the reasoning behind such ideas. The earth's tectonic plates move in response to the sleeping dragon's dreams. Volcanic eruptions are but the troubled snoring of the fire-breathing drake. Oil is tapped from its veins.
While there is something definitely creepy about this idea, there's also something appealing to it as well. I like to think to of the Earth as an organism that is simply too large for us to fully comprehend. Considering that our entire existence plays out on such a thin layer of its surface, it wouldn't surprise me to learn that there is a great deal more to our Earth beneath her skin.
However, I do hope that the dragon doesn't wake up any time soon.