I have seen a surprising number of Secret Wishes over the years with a lack of glitter - oddly most of them seem to have been UK based [but that's probably a coincidence]...its probably just that her plastic batch didnt have a good distribution of glitter - a different quality of plastic would also explain the variance in colour.
She runs around $6ish at the moment on ebay - one of the G3s who has crept up a tiny bit in price recently...I honestly am not certain if the glittery-less one would run more but I would guess probably not.