fyi they apparently use 10.4 kwh not 8kwh. http://gm-volt.com/2010/10/26/chevrolet-volt-will-utilize-10-4-kwh-of-battery-to-achieve-ev-range/
so i guess that's 65% for the volt versus 80% for the leaf?
As for the crux of your post, fine that may be a valid point; however, it doesn't really...