You know, at the end of the day, I have just always thought tomahawks are kind of cool. I can offer no justification to buying one beyond that, because I tend to agree that if I really need an axe or a hatchet, I want an axe or a hatchet. Not that I am ripping on people who do combatives with tomahawks, but the chances of me using a tomahawk in some sort of battle situation are so close to zero as to be statistically irrelevant. And, while I do enter the piney deep on occasion, I can't see me using (more specifically, choosing to use) a tomahawk for something that my big camp defender or a hatchet would do better/easier/faster.
But man... they are cool. I actually do have a hawk that a buddy of mine made for me, but that has sentimental value and is not likely to be used for anything beyond appreciating a handmade gift from a friend.