Girl #1: Is Cuba part of North America?
Girl #2: Do they speak Spanish in Cuba?
Girl #1: Yes.
Girl #2: Then no. Cuba is not part of North America.
Guy: What about Mexico? They speak Spanish in Mexico.
Girl #2: Mexicans are illegal.

http://www.overheardatmcgill.com/archives/2007/04/19/same-rationale-used-to-keep-quebec-out-of-north-america/