Every year the PM leads a ritualistic blood-letting, and all the anger pours out from each canadian in the form of maple syrup. They bottle it and distribute their soul's malfeasance to other nations. The residual bad-vibes are soaked up by the naturally hate-absorbent Canada Geese, and it is rained down upon the US as they 'migrate' (read: fumigate) over our heads. (Real answer: I have a theory about harsh climates naturally leading to particularly hospitable cultures. I haven't done enough research to back it up, but it seems like places that are Snowy or Hot or Hard-To-Live-In tend to have really friendly people.)
You are on to something with the Harsh Climates Breed Nice People Hypothesis. When Mother Nature can fuck you up with no warning and at a moment's notice, you start to being nice to others as a matter of course... you may need to shelter in their unlocked car from a bear, or borrow supplies, or rely on a neighbor to help dig out the snow in front of your door...
about the maple syrup, I heard an expression the other day on the radio. Someone was talking about how wonderful Canada is. The reply was, "C'mon, let's not maple-wash everything." Like other countries, Canada has a less than admirable side. Let's not maple-wash everything.
Can't speak for the rest of the world, but we shovel our neighbor's walks in the midwest! Dad used to drive a big fuck-off truck, and we'd drive around town during blizzards to pull people's cars out of drifts. Haven't done it since that rust-bucket bit the bullet, though. We've finally acknowledged that 'Nebraska Nice' doesn't bring in tourists, but it's still a way of life :)