Disseminating a narrative through any possible medium and in any possible aspect of life, in order to make sure it is constantly reinforced into in the minds of people and accepted as natural.
Having a person surrounded by a constant repetition of the same narrative from countless different sources all around him slowly makes that narrative undistinguishable from reality. Securing their presence and influence into all kind of mass-media gives the elites the ability to do precisely that, by pushing the same messages not just through formats specifically intended for information purposes (like newspapers, talking shows and documentaries) but also subtly inserting them into commercials, fiction and/or entertainment; last but not least, countering the rise of alternative media (like the Internet) by invading them with mainstream news outlets, "debunking" of alternative informations, or fake (i.e.: controlled) ones.