You know, like some films aren't, some novels aren't... Plus, Eddie Campbell draws dog-fuck ugly people for the most part. They'd probably bitch over the fact that it doesn't look like Jim Lee or Jim Balent or Joe Linsner or whoever.
'From Hell' is about a lot of things, and one of them is a Victorian attitude to sex that meant that the brutal murders of certain people didn't matter because it was just better not to talk about that sort of thing. Oh the irony, oh the etch-a-sketching, oh the joyful, rosy-cheeked capering!
Until then, if you don't like it, don't read it and let adults make their own choices.