In the past 30 years, the percentage of people who graduate from high school has gone from 50 to 80. At the same time, more people than ever before see education as a lifelong process, rather than something that terminates with high school or college. As a result, people are more self-confident, more willing to look things up themselves. Indeed, people used to think that they'd be better off if they abdicated to experts, because the experts were so much more knowledgeable. That's no longer so.
People feel empowered in ways they never did, which leads to a second consumer demand for mastery.
Take a look at the Boston Herald. On any given day, the Herald features at least one world-class medical news story. Perhaps it's a version of a New England Journal of Medicine story on the effects of hormone therapy on women. But there's tons of health information in the Herald, and it wouldn't be there if that population wasn't interested. Their employers take a portion of their salaries and buy health insurance on their behalf.