As someone who has spent decades on offshore platforms I can tell you that if a bunch of idiots tried to board without permission I would be extremely grateful to anyone that hauled their ar***s off to jail.
I suspect if the same tactics were tried in the north sea it would be seen as a potential terrorist attack and the response would be far more forceful.
I have no argument with greenpeace spreading their message but if their means of transmittal puts others at risk and breaks international law they deserve everything that they get.