As someone else pointed out, there is some degree of defining "acceptable" behavior - for example, don't dangle infants over balconies or drive around with your children not secured in their seats properly. 

Another factor is the way television news is covered.  Years ago, network news weren't ratings driven.  Network news has become a profit center for the networks.  That can prevent any investigative reporting on any sponsors.  Except for news shows, such as 60 Minutes, we don't see news items that last much more than a minute.  In the past 20-25 years, there's been this belief of a MTV generation, where video images have to be fast and catchy.  With that mindset, it's easier to say some celebrity was arrested for DUI than something that is more important, such as whether the "surge" in Iraq is working.

I think there's another issue at play - keeping peoples' minds off of the issues that are more vital to having a democracy.  Not only celebrity "news" does this, think how often CNN Headline News, MSNBC, or other cable news stations disrupt their schedule because there's a police chase happening in Los Angeles, or, like the other day, watching an airplane fly around the Miami airport to use up fuel before making a landing because of a problem with a door covering the front wheels of a plane.