The example of crime in the second post is a good one for this discussion. Our view of how safe or how dangerous our neighborhoods are will be shaped by media, from news to film.
The same holds true for other examples of "life as presented through media", where people at large will reflexively compare their own lives to the lives they see depicted in the media.
If you watch documentaries on poverty in America, you may begin to think that 1) you and your family are actually doing very well compared to those who are living in poverty and 2) America is a rather poor country. Alternatively, if you watch documentaries on the wealthy you might come to the opposite conclusions about yourself and America.
This is simply to say that the media provides us not only with information but with reference point which we use to define our social position.