A Canadian is telling people not to pretend to be Canadian. That should be reason enough instead of arguing with me about why it doesn't matter for someone to fake their nationality. Would it be acceptable for Americans to pretend to be British or Irish?
What an individual wants to do doesn't bother me at all since I'm not faking a nationality. It's a backpack patch. And when I've partied with Canadians in person, I've never heard a complaint. I have been told that it's probably a smart move in some places.
Saying it "probably is smart" isn't the same as saying it's ok. It's not ok.