So, actually the question is: How come there are so few pilots in Canada?
Or alternatively, why there are, proportinally, so many in the UK: A legacy and inspiration of the war combined with the product of a reasonably wealthy capitalist society. Couple that with an unconquered teritory which had the need for hundereds of airfields. Just ripe for derring-do types to build the roots private aviation. This is also the reason why the UK has 1/3rd of all privately registered a/c in Europe and why the UK is also at the forefront of the motor racing industry (inspite of Silverstone!).