Google ads will work on the newspaper medium. Traditional newspaper ads are distruptive marketing: the content of the ads is not similar to the content. Google will have content sensitive newspaper ads, which will work a lot better.
Ads don't need to be relevant to content. That's the ultimate mistake with adwords. Ads need to be relevant to readers. WSJ readers are, with high probability, richer than the readers of other papers. So they want bentleys, no matter what they are reading about.
Print subscribers' average net worth: 2.4M.
Come to think of it, though, those numbers could as easily imply that their average reader is very old. So maybe they are backward.
I'm sure more super-rich people read it than super-poor people, so this average is a bit aliased.