[eftpotrm]

But, there is arguably no more commonality between the people of Norway, Portugal and Bulgaria than between Canadians, Mexicans and Chileans, so why can we call the first group collectively European but not the second collectively American?

The standard English nomenclature for residents of the USA (which I belive isn't so much of an issue in other languages) is confusing.

[bluedanieru]

I'm not making any claim that it's logical or follows a pattern. Are you sure you really mean "confusing" though? As in, ambiguous? Because it really isn't for most people, even those that don't speak English very well.