I used to Heart Radio

[BigV]

back in the day, I was the IT department. And the reasoning for blocking stuff like that wasn't the impact on bandwidth, it was the perceived impact on productivity. The PHB co-owner decreed that there was to be no non work browsing whatsoever, no radios or mp3 players in workspaces and that cell phone calls of a personal nature were to be made/taken on scheduled breaks only and not in the building.

I don't miss that insanity.

eta:

They're watching and noting all the computer / browsing / internet activity for all users at all times. I'd bet lunch on this. In case you weren't jaded/paranoid/cynical enough already.