One of the worst cuts I ever got was from a Swiss Army knife. On the other hand, I've been fortunate not to injure myself with a Fubar, crowbar, pick mattock, double bit axe, or my larger knives. I have broken both big toes on plywood when it slipped straight down onto my boots. You can get hurt from some stupid stuff.
I'd be more inclined to use a spike hawk than hammer with the butt of a medium blade. It's more a matter of knowing the hawk would likely be used more to one side to get the full swing when dropping the stroke with my hand near my ear.
Carry in a belt is something else. It's the same as carrying a knife simply shoved under the belt, no scabbard. Not my cup of tea. Even the American Indians made scabbards for their blades. They carried the hawk in their hand, or cradled. In that position, it became more symbolic, as an expression of rank - the same as the mace of royalty, which became more presumptuously known as a scepter.
As for whether a digging stick should be fashioned on the spot, nothing wrong with that. It depends on if or when it's available, too, and it also ignores a benefit of the one piece hawk with integral handle - the end of it could be used in exactly the same way if fashioned appropriately. The Gerber Downrange has it's nail puller on the end of the handle, so does the Stanley FUBAR. Some hawks leave the end exposed in a spike,too. In the case of the Condor TRT, I can see beveling the end of the rolled steel handle to create a digging implement. No need to search out and trim down a stick, just get after it already. It's a bit redundant tho, literally. You have a spike on the other end, if you are so inclined.
No sense that it come back to hurt you. In that regard, even a small blade becomes dangerous, and the military exercises due regard to test sheaths and see that the user isn't injured by something as rough as the tumble from a parachute landing fall. If your gear is so difficult that it could hurt you even when it's holstered, take precautions. Plenty of the CCW crowd does by only carrying a pistol with an appropriate safety. Tripping over a root that more likely needs a hawk takien to it just to be injured by the tool itself in the fall would be an embarrassing end to a trip in the woods.