You don't say her breed, but I have noticed the same thing in my Siberian Huskies - but only the females. It seems to mean that they would like more, but are less brash about asking for it than the males.
Maybe when we stroke their head and ears it reminds them of when their mother would lick them to clean them when they were pups, and the paw-swipe is very like what they do when they give themselves a wash of the face.
Maybe when we stroke their head and ears it reminds them of when their mother would lick them to clean them when they were pups, and the paw-swipe is very like what they do when they give themselves a wash of the face.