Use of Haka by filmmakers

A lot of threads refer to the use of the haka by the real rugby team, and while I do think that if they want to do a haka they need to come up with their own and not use ka mate, this thread is about the use of the haka in the film.

After seeing the trailer, I thought the film would give me a reason as to why the team performed the ka mate haka specifically. ie. I expected a reference to new zealand and the all blacks, but there wasn't one, which I thought was disrespectful. Anyone not familiar with new zealand or rugby would assume the haka was a highland rugby thing exclusively, which I think is inappropriate to imply.

Not only that, but they made it seem as if non-highland rugby teams were ignorant of the all blacks and the haka, which I found odd. Surely if you play rugby, you also follow rugby and are aware of the all blacks, and thus when you see a high school american team performing the haka, you don't put them down by denigrating the haka, but if anything the team for being posers.

Also, the team played Scotland in the movie, which made me wonder what would happen if they played New Zealand.

Haka aside, what an awesome coach.