So are Kul'Tiras humans and Stormwind humans.
Plus there are lore basis for build/posture differences between high elves and blood elves, chief among those are the myriad of possible ways the high elves could have done to dealt with the effects of magic withdrawal, as they refused to follow Kael'Thas teachings, while the blood elves embraced said teachings, draining mana from living beings, and the fact they were not affected by fel magic like the citizens of Silvermoon.