Sorry, that is your typical American way of thinking. The relevant Norwegian Unions are part of ITF and DO look out for their downtrodden comrades. (Hard to believe, I know)
PS> They actually stepped in to hold up an American flag offshore vessel from leaving Norway because they didn't have a propped wage agreement, or comply with MLC'06.
Norway do not have anything like the Thialf, Saipem 7000, or the new Pioneering Spirit to do the type of operations require to install or remove platforms, or lay large pipes.
There is no way the Unions can or will demand that the full crew of such vessels shall be changed to Norwegians for the few weeks or months of the year that they are working in Norwegian waters.
Likewise, to demand that Norwegians, or Norwegian Contractors be engaged to do the preparations for lifting/removal is not in the cards either.
The work to Plug and Abandon the wells are carried out by contractors offering the best and most cost effective methods, regardless of whether the Contractor, or rig used, is Norwegian or not.
At the moment there are rigs owned and operated by American, Italian, Danish and Chinese companies working in Norway.(Or stacked and ready to work anywhere in the world)
The Law requires that work on fixed platforms has to be carried out according to Norwegian rules and regulation. The personnel has to be paid Norwegian wages and work under Norwegian conditions, which does NOT imply that all workers HAS to be Norwegian nationals. (They have to have Norwegian work permit though)
Oh yes, I almost forgot; they do work 2 weeks on/4 weeks off schedule, regardless of nationality of the person, or Contractor. Maybe you find something wrong with that work schedule too???