Is THIS how you imagined the vampires?

[davem]

Originally Posted by Morthoron

We can't expect Morgoth's minions to fly about like overgrown canaries or laden swallows, it would be unseemly, and certainly not the 'look' the Dark Lord was seeking..

Of course, we do find

"Thus Sauron yielded himself, and Lúthien took the mastery of the isle and all that was there; and Huan released him. And immediately he took the form of a vampire, great as a dark cloud across the moon, and he fled, dripping blood from his throat upon the trees, and came to Taur-nu-Fuin, and dwelt there, filling it with horror."

Which seems to imply Sauron flying ('a cloud across the moon' 'dripping blood from his throat upon the trees').

Or am I misunderstanding your point?