Speaking for myself, I mean no disrespect when I refer to people of the US as "Americans." It's just a more expedient way to refer to "the citizens of the US" which is a bigger mouthful. I can see how people in Canada might be offended, since they are also part of the North American continent. But even most Canadians I know don't bat an eye when I refer to US citizens as "Americans." It rolls off the tongue easier and has fewer syllables. "US citizens" = 5 syllables. "Americans" = 4 syllables. Sometimes I just call us "Murkans" (more fitting these days) which only has 2 syllables. It's probably just a sign of how lazy we Murkans are