Uh. WRONG. Do the math. There are are a lot of factors going on here - not least the current network usage (i.e. are there network applications being run directly from one or more servers or other serious bandwidth hogs? It's not uncommon for databases to be run that way and there's also digital telephony to think about), the speed of the network (100 base T is still commonplace - not every company can afford to upgrade their infrastructure to GigE just to accommodate stuff like streamed music), the number of users likely to connect to the stream, and the size of the files being streamed (high bitrates consume bandwidth big time).
It always amuses me when folks who don't actually have to manage a corporate network for a living turn round and assume that just because their piddy little LAN at home can handle it, the big network at work MUST be able to handle it with ease - it's just the network admins being 'difficult' or 'incompetent'
. It's not until you actually try to manage a corporate domain yourself that you are forced to start looking at the numbers and work out where all the bandwidth has disappeared to. When I first took over I.T. at my current place of work, we had just such an issue - one office down at the far end of the building was having a hell of a time using our corporate database, which runs centrally from an installation on the database server. It was a bandwidth issue and the solution was very complex - it included re-wiring part of the building with fibre, upgrading a couple of network switches and reducing some of the really bandwidth-hogging traffic. I'm not exaggerating when I say that it was a two-month project which took an awful lot of planning. Even now, there are limits to the bandwidth available as the bottleneck is always going to be at the central point of the network - it wouldn't be hard to clog that up with traffic again.
Most network admins would love to be able to say yes to these kinda requests (hell, we'd like to stream music too!), but it ain't always practical - it depends on a bunch of complex factors which are going to be different for each company. Wanting it to be otherwise don't make it so, sorry.