Wow! That is crazy but true. I think you should ask Nikon Canada since they are the only ones that can answer that question.
Comparing the List Price or SRP of the batteries at W ower%20Accessories" target="_blank" rel="nofollow">Nikon Canada to Nikon USA the EN-EL14 is $89.95 CD and $40.95 USD though other batteries like the EN-EL18 ($199.95) is less expensive in Cananda than the ($220.00) in the USA.
So the pricing policy doesn't seem to have a pattern. Good Luck and Enjoy your Nikons!