Most major media sites use AdSense or something like it. (NYTimes.com and Washingtonpost.com are two such sites that I visit every day.)
Maybe you aren't their prospect. :-) Seriously, advertisers spend billions of dollars per year on AdSense, and it's a direct-response medium that allows advertisers to track their ROI (return on investment), so they wouldn't be spending the money it if it didn't pay off.
That may be true for some topics, some types of content, or some audiences. Many publishers earn far more than that, however. If you're publishing a site for an audience of people who are researching ways to spend their money, for example, you're likely to earn more than if you're publishing a site for Britney Spears fans or hitchhikers. In the AdSense world, as in the world of print and broadcast advertising, audience motivation has a lot to do with ad rates.