In North America and Europe, it's common for motorcyclists to quickly layout routes when touring using google maps. They (google) have made a UX that makes it ridiculously easy (as compared to something like Garmins Basecamp -which should be used as shiny example of how not to design an UX) The issue is that you cannot directly save the maps in GPX format to upload to your GPS. So thiers a world of work arounds, some easy, some not, to get a KML file into your GPS.

If it supported GPX natively, you would likely capture the entire North American and European touring market in one fell swoop. I'm guessing you (google) never asked which kind of goes against the entire point of this article