Have you noticed which groups of working people listen to music while working more than other groups?  I realize technology ie.  Nanos and MP3, etc. have made it easier than in the past generation. Here's my point, what I've seen, is painters and some construction workers and similiar trades are known for having a radio covered in mud cranking out their fav tunes.
Sitting at keyboard also lends itself to wearing a set of head phones with a numbing volume of whatever the air is full of.

In response to "...your not a sour puss from being frustrated, listening to music soothes the savage beast".  Are you suggesting.....:-)

It may be of interest to you that a group actually exists called Savage Beast.  Have a look and read:  http://www.cato.org/pubs/policy_report/pr-jf-sx.html