If I wanted to fly a G registered 747 then I would indeed convert my FAA CPL/IR and add an EASA Type Rating.
However all I want to be able to do is fly my N registered Rockwell Commander to France in the cloud when I feel like it. It would be a bit rich to say the least if an American could fly his RC from England to France in the cloud, yet me being a brit couldn't.
Actually I would anyway, I have JAA PPL+IMC which may become an EIR so I think I have covered myself quite well.