In a post about Google's agricultural-mapping expeditions, commenter skwash suggests that Google's snapping shots of business-free rural roads so it can create its own geographical database, shutting out map providers TeleAtlas and Nokia's Navteq:

You have to consider the fact that Google has to pay to license all of their street data from NAVTEQ and TeleAtlas. By essentially photographing the view from the street, Google has access to nearly everything they need to re-create the data set. Street names, mileposts, exit numbers, etc can all be pulled from the images. Combine this with their recently announced Map Maker and Google has their own data set with accuracy as good or better than their current sources, and they don't have to pay ridiculous licensing fees. This doesn't even account for the fact that Google is striking deals with local government to publish geo data as well, or that Google is using Street View cars to collect 3D data on buildings.)