Where are the bearings in thru axle hubs?
Many thru axel designs use cartridge bearings, which are not servicable (one replaces the cartridge bearing-- no more loose balls smushed in a greased filled cup and held in place by adjusting a cone nut).  Here and Here are schematics from Shimano of a rear and front hub featuring thru axels.  This particular model uses caged bearings, and I've selected this for clarity as the bearing balls are obvious and not hidden within a cartridge package.