Commercial radio stations worry about losing listeners and ultimately advertising radio from pirate stations. Perhaps they should stay more relevant to their listeners. Radio 1 was initially heavily influenced by beginings in pirate radio.
I spent many years working the night club scene and one of the things that people found appealing was the "underground" attraction. Cream became a victim of this; once things started getting too commerical, many original customers stopped going.
Check out the MB21 tranmission gallery to view many of the commercial masts.
Radio 1 is Holm Moss: http://tx.mb21.co.uk/gallery/holmemoss/
Our TV signals ultimately come from Winter Hill: http://tx.mb21.co.uk/gallery/winterhill/index.php
Shame none of the pirate stations had a set up like these!