pirate radio stations have a long history especially in London, they frequently try to take them down, but so do rival radio stations try to take out their competitors radio stations too.

Anyway, the FM band is still in use, see the furore over iTrip or similar devices that were at a time banned in the UK as the law said you needed a license to broadcast on FM.

The FM band is still in use and even when radio goes digital AFAIK the idea is that the FM band would be available for alternative use once radio stations no longer require it.