Wall-worthy marketing

There is a trend I've noticed among restaurants and small businesses that highlight a simple truth about the value of advertising vs. public relations. On the walls of many restaurants and small businesses are framed copies of large newspaper or magazine stories about the business. Usually it is a story about the opening, in the case of restaurants, but often in businesses it is a series of reprints from prominent media or trade magazines.

This leaves one wondering, "why don't they prominently display their advertising in a similar manner?" Of course the answer is very simple - credibility. The restaurants and businesses know that third party endorsements by way of the media are much more credible than self-promoting advertising.

Which again leaves one wondering, "why do so many businesses spend so much money on a marketing function that isn't wall-worthy?"