WHAT?! What part of WOLF don't they understand???? Lupin does not turn into some freaky half-human two-legged walking beast! He turns into a werewolf. Have they NOT read the books???
Now, other than them wanting the whole Padfoot/Moony angle, I don't get this argument. 1) If he was turning into just a normal wolf and not some monster, don't you think JKR would have mentioned that in the books? Since "tall, two-legged, hairy monster" is the werewolf norm, if it was something different wouldn't that get a mention? But the more important is: 2) JKR has a big hand in all of the movies, does she not? She approves the scripts, she's on-hand, etc. Her book-writing has been delayed by the amount of time she put into working with the movies. If she did not want Lupin to be the monster kind of werewolf, think she'd just shrug, say "meh", and wander off to hit on Alan Rickman?
Bah. Take a chill-pill, ladies.