warpus
Sommerswerd asked me to change this
The biggest difference in that regard between the USA and Canada is the century between the two of them. The US Constitution is a constitution of philosophers and idealists, concerned with doing things the right way, with great principles and whatnot. As such, it is focused on limiting federal powers in the name of democracy, division of powers, etc.
The Canadian constitution is a constitution of industrialists and rail barons, and it was written to get the job done, not to defend principles. It also helped that they could peek over the border to see the parts of America that didn't work so well. As such, it is focused on attributing each possible power to the level of government best suited to dealing with it efficiently (and then making sure there are rules on how to split anything that they might have forgotten, and anything that might change category, and so forth).
This resulted in a much stronger federal government to start. Anything congress can do, parliament also can, and parliament also throws in a few extra powers congress only wish they had. For example, parliament has exclusive power over all of criminal law and banks. Oh, and the definition of marriage, which came in handy about a decade ago. Throw in the fact that the Peace, Order and Good Government clause is basically Interstate Commerce on steroids (and I mean how the federal government read interstate commerce)...
So while the provinces are very defensive about the federal messing with provincial powers, their powers are a lot less likely to limit the federal government.
Funny, I never looked at it that way, but now that you've written it out, it makes perfect sense.