Iimagine it has somethign to do with an "international" order. I used to work at a place that sold online and authorizing non-US cards was a pain. I can possibly see for additional verificationif the order was from someplace like Afghanistan, Libya or the South Pole but Canada? Inever understood the need for such difficulty. I can't beleive that I am actually speaking in defense of Nitroplanes for once but I imagine it is just some stupid formality with their credit card processing company.