Every film producer or tv producer can tell you that the most important part of a visual product is the sound.  There are so many effects you may watch on the screen, big or small, and you are pulled, moved, swayed by the aural experience of the production.  How does an emotional scene feel without music, or even the wrong selection?  How does an action film captivate the audience if they are jolted with the tension and excitement of a riveting sound track?  It simply doesn't.  Although, history proved that it may work occasional. e.g. Alfred Hitcock's The Birds (1963) didn't have a sound track.  However, this is a rare find.

A commercial doesn't tag your attention without the right hook and music.  Even news agencies have been using the power soundtrack to broadcast presentations and CNN, MSNBC, CNBC, CBS, FOX, ABC, NBC all have their musical signature musical tags that help you identify their name.  Branding.