We still believe that humans are ultimately incapable of living peacefully, and that we need some higher order to help us see the light. Historically, this was God and Jesus' role, though I think people had big misconceptions that God would provide everything, and we could be the lazy bums we want to be. Recently, it has become less popular in our culture to associate oneself with the Christian faith, so a new harbringer of lazy times was needed instead, and aliens fit the bill perfectly. Already New Age, aliens quickly took the place of religion in a lot of peoples' lives. Aliens also took the place of the faeries and goblins which permeated European culture over a century ago.
People are prone to being highly influenced by what they read, see and hear.
When I was younger, I was heavily into the UFO craze. I read on the subject constantly, and every night I'd have some nightmare of encountering UFOs. But they were just nightmares. Perhaps I found them too scary-looking even for my subconcious to conjure. Concerning the issue of missing time, readings of a psychological nature and personal experience would suggest that missing time is a natural psychological phenomenon, where the individual is in a kind of hypnotic state, and is not conciously aware of time passage.