I distinctly remember my crayons saying 'grey' in kindergarten
america is just a really unnecessarily independent country. america drives on the other side, different measurement system, etc
Interesting to note that the majority of countries drive on the right, not the left.

Red is right, blue is left. Notice how most of the countries driving on left are former British colonies. So in reality... you guys are the ones behind the curve driving-wise.
Also, the customary system just makes more sense to me. Not the conversion part, but the base units. Meters and kilograms are too big to describe most things I describe on a daily basis, and kilometers are too short. Feet, pounds and miles are just right.
But your grammar rules make more sense than ours. If English adopted American spelling and British grammar, we'd have the perfect language.