I agree entirely that AM radio is well past its sell by date and will not get a large audience like it used to. However, in the case of offshore radio i think that the fact that as far as a government is concerned , the platform is not important and any attempt to broadcast freely over a wide area would be seen as a threat. Taking a photograph of a policeman in parliament square is hardly threatening but if you're spotted doing so , you will be questioned and asked to stop doing it and possibly arrested. The point is that the government are complete control freaks these days.