I bet most people aren't thinking about eigenvectors when they are looking at Google's search results. The user does not (and should not be made to) care about sophisticated algorithms; only utility counts (in business, of course, not in research.)
Yes, one could. Though it isn't the question you originally asked, and so you shouldn't be surprised when you don't get an answer to that question. The question you asked was "why aren't startups using sophisticated algorithms?" ;-)