Being in the Pep Band at RPI I know that we play both anthems before each game.
The Canadian first and the American National Anthem.  I believe it is the only
way to do it.  There are many Canadians in the league.  Thus I see it fair that
the arena's play both anthems to please all the players on both teams.  They
do it from time to time in the NHL....I think that they should do it all the
time in the NHL and the NC$$.
 
At RPI usually the fans sing the words to the Canadian National Anthem as much
as they do the US National Anthem