Spydo - I have a 16 oz Vaughn trim hammer with a wood handle that I treated with car wax, decades ago and I've yet to do anything else to it.
I prolly have 15 or so hammers and those with wood handles received the car wax treatment.
Yeah there is a lot to be said for many of those older USA made tools with wooden handles. Now I do also like Estwing's tools too which are also still USA made but there is something about the feel of a well balanced, wooden handle that is hard to beat. I don't know who made the Sears Craftsman's hammers but they weren't bad either.
I remember when I was just a kid growing up in the 60s it seemed like most of all my dad's tools had wooden handles at that time. I've often wondered what those factories at that time recommended for treating the wood handles on the tools they made?