That was just one of the points I thought made little sense. The producers said that they changed the character because they liked the actress (who is German and can't speak without an accent) and I can't imagine that they want to change the events of the end of ASOS.
and why can't a Sand Snake be white exactly? The show been veering off book so much, why can't ye old Dorne boy charm himself a Highgarden milkmaid and get a white daughter?
as for Craster - ok, he doesn't need to be filthy looking, as in dirty. My bad. BUT he still doesn't sound or look creepy and bastardly and just batshit as the book version... If the scene before didn't bring up daughter-fucking and the mystery of what happens to the sons... I never would have known the guy is batshit from the way he holds himself
Watch Frey - in first 5 seconds all the creep~factors are shown loud and clear. Craster, not so much
As for Craster, you give a perfectly good reason why he's not like that. Because he would be Walder Frey the second. Therefor I don't think it matters much. He still has insanely creepy habits and is not very pleasant to be around.