Bill
I think the axe is used for cutting meat. The spike end is stuck into a piece of wood or the ground with the ctting end up in this way one can just run the meat across the cutting edge to slice it up. when carrying meat back to the village it can be placed on that back spike the axe is then slung over the shoulder spike up.
See link
http://www.vikingsword.com/vb/showthread.php?t=7438