If sticks could penetrate bodies so reliably, we'd never had the need to develop sharper weaponry made from bronze, iron and then steel. It bugged me to no end, that at the end of the whole thing, a kid, from a lower position, with no particular upper body strength to speak of (men develop theirs during and after puberty), pierced through a body without effort to speak of... So damn unrealistic. At least with the penetrating of zombie skulls one can make the argument that being dead + virus weakening the bone etc.