Before nail-guns and drywall screws you used to see a lot of octagon hickory handles. The shape seems to be to take less effort to grip and still maintain control. Important if you are hammering nails all day. The last hammer I bought with a factory octagon handle was a Vaughan 16 oz claw, and that was over 30 years ago. Fortunately, The Beaver tooth handle co. still makes octagon handles. So now all my wood hammers have octagon handles. From the 32 oz ball to an 8 oz claw.
You just have to remember wood for nailing, steel or titanium for demo work.
