The producers don't seem to mind gritty, overtly creepy magic, like wights and wildfire and Melisandre's various enchantments (especially because the latter allow for T&A, which is a plus in their minds), but dreamlike, suggestive, prophetic, and subtly eerie material is pared down to the minimum possible. It's pretty obvious that some aspects of the series' overall tone appeal to them more than others. "Violence and intrigue? Yay! Mystery and wonder? Meh."