In addition to throwing, some outdoorsmen might prefer a hawk for skinning/butchering work. Many hawks have an ulu-like curvature to the blade that some might prefer for game processing. Of course, Gransfors makes a Hunter's Axe that others might like better than a hawk. It's probably a matter of personal preference.
You also frequently hear the argument that it is easier to field repair a broken hawk handle than replace one on a hatchet. Fortunately, I've never had the need to make a personal comparison.