Someone please explain to me how a movie like Paranormal Activity is doing so well...

I just got back from watching it. 15 minutes in I was falling asleep, it was only 9:00 pm, and I hear OMGOMGOMG *GASP* all around me the whole time. Seriously, I knew when something was going to happen... and I didn't even flinch except for the end but I was half-asleep ^^;;

There was nothing scary about that movie and I can get scared easily, so... anyway, I'm tired.