Not true. Google Habs booing anthem and you'll see that it happened more than once and for numerous reasons. Mostly because US Anthem = American team we hate and want to beat. But if I'm also not mistaken, didn't the Habs fans booed the anthem just after George Bush Jr. was elected? Reason why I think it might happen with Trump.
http://www.cbc.ca/news/canada/montreal/don-t-boo-u-s-national-anthem-habs-gainey-1.775463
I'd be surprised if it gets repeated we are a more understanding crowd now?