It is legal, but does not stop it from being a con.
Years ago I stopped people from playing the radio at work, as there was always a fight about what station to listen to. So there are plenty of negative effect to music.

If you play un signed bands, music that is not copy righted, there is nothing they can do and there is plenty of it on the net. Or of course you can listen to talk radio. I have to assume if you use an Ipod with ear phones, no one other than the individual can hear the music so no broadcasting.

The internet is still covered, any copy right music needs a licence.

The answer is to Ban radios in the work place, then all the DJs will be talking to them selves, no one will hear new muisic and therefore sales will go down.

This is a seriously counter productive licence if people treat it in the correct way. Don't play music at work and don't buy music in protest.
The licence will then no doubt come to an end, at least when it is applied to workers just listening to their radio, or music CDs they have already paid for.

This licence existed since 1914, but this is now the 21st century, things have changed a lot since then, inlcuding the amount of money they make from music.
Write to your local MP to complain. Laws can change.

Tony