"I don't quite see what ear-piercing (or indeed female genital mutilation!!) have got to do with the case."

Nothing, bar the fact that parents the world over love and desire to do the best that they can for their children. We are each powerfully personally influenced by our respective cultures of course.
However, imposed cultural expectations pertaining to girl children in particular, are not always very sexually liberating or indeed helpful to the expression of their unique individuality, which I would argue, is bound to be far more inspiring than any supposed "cultural tradition" that their elders and betters might wish to inculcate them into - sorry for the "irate feminism" there Suibne ;-)