Allie kiwi, blame Napoleon for the driving on the wrong side of the road thing. For some reason he decided to dispense with centuries old tradition, and the Americans followed suit. Dawn of a brand new world and all that. At least the Americans had and still have the sense to resist metrication.
And don't you think the Americam way of spelling "honor" , "color" etc is much closer to the classical roots of these words than the Briitish way is?