Here’s how an anonymous black hat SEO consultant justifies the existence of his industry:
I think we need to make a distinction between two different kinds of searches — informational and commercial. If you search ‘cancer,’ that’s an informational search and on those, Google is amazing. But in commercial searches, Google’s results are really polluted. My own personal experience says that the guy with the biggest S.E.O. budget always ranks the highest.
That’s from a long New York Times piece on search engine optimization.