No it is not necessary, just personal preferences. I've used hide glue and Tite Bond 3(waterproof) to glue skins to wood, sinew, and fabric. For instance with osage, I prefer to allow the color of the wood to penetrate through the skins for contrast, while other will color /stain the wood so it doesn't show through the skin. Just remember to size( allow the wood to absorb the glue) the wood with whatever type of glue you use before putting the skin on. Good luck.
