Traditionally hand made or low to medium volume (dark) oak was stained, the grain filled and then French polished. Industrially made stuff was also French polished until the 1920s/30s when the industry went over to cellulose. After WWII the move was to pre-catalysed and 2-pack lacquers (less explosive). So no wax in the majority of cases, at least not as it came from the makers. "Blonde" oak, which is also lacquered in most cases, is a modern invention. If you'd ever had to wax a run of large items of furrniture you'd maybe understand why waxing is the preserve of low volume/pine furniture outfits (although these days you can spray apply wax over an initial sealing coat, which is what I believe Oak Furnitureland might well do)
Wayners was right when he suggested a solvent. Another one to try is acetone, but in general once you have waxed something you can never remove all of it - any heat applied through, for example, sanding will cause the wax to.penetrate further into rhe grain and ruin any chances of staining the timber (it comes out mottled)