It seems to me that NCL had a couple of options...
a) have a letter distributed to every passenger, explaining exactly what Uk law has been introduced and when - quoting the exact wording, so it shuts up all the doubters, removes all those queues at Guest Services, ensures no one wants to remove gratuities, gives people on this thread nothing more to talk about... and so on. If I were an NCL Manager I'd be sorting that out pronto.
OR...
b) admit NCL have taken their eye off the ball (eg not paid a bill in time, not applied for a licence... or whatever.) Apologise. Make a nice gesture. Move on.
Unfortunately they have gone for...
c) Don't explain. Don't admit anything. Don't provide any evidence. Upset people. Allow things to fester and get worse. Ensure your hard-working, lower-level staff get a really hard time because of your own incompetence or cowardice.
Honestly... what sort of company, with any sense of pride or responsibility, would opt for C?!!!