After reading about the riot in Vancouver, British Columbia (following Game 7 of the Stanley Cup finals), you would think you were in Los Angeles or some other big American city.
Several years back I attended a Spokane Chiefs hockey game in a Canadian city. They not only booed the American anthem, but after the game was over and their team lost, the fans started to throw empty beer containers at Chiefs players.
A security guard was standing next to me. When I asked him what he was going to do about it, he just turned and walked off.
I have watched other hockey games on TV and heard the Montreal fans boo the American anthem. We Americans respect the other anthems.
I have several Canadian friends and they are wonderful, respectful people.
I guess the Vancouver fans are poor losers.