Often unable to beat the media competition armed with retargeting and other vast, cheaper-than-premium methods for reaching targeted audiences, a growing number of publishers is now joining the trend, purchasing cheap media where their known audience is known to be, effectively growing their audience on the cheap with non-prime content avails.

While more than a year old, a study showed in 2011 that one in five publishers was already doing one form of audience extension or another, and that another third or so planned on trying it out. AdMonsters reports that Forrester deems the practice to account for 5 percent of today's media buys.