It's worth noting that there is a great conceptual difference between believing in intelligent extraterrestrial life and believing that UFOs are alien spacecraft, and that their pilots abduct people late at night.
For one, that a species could evolve independently from our own on another planet and look exactly like us, only with bigger, blacker eyes and pale skin without deliberate intervention is utterly untenable. As another poster already pointed out, such depictions of aliens are too similar to past supernatural figures to ignore their psychological, archetypal significance.
Put another way, extraterrestrials would look a whole helluva lot different than we do. They'd probably have some kind of fur and eyes, since these evolved several times independently on Earth, but there the similarities would end.