The Cabin in the Woods

I just watched the movie The Cabin in the Woods, which just lauchned in the cinemas here in Austria. It's a teen horror film by Joss Whedon (known from Buffy, Dr. Horrible's Sing-Along blog, and of course Firefly). The film is actually very good IMO, it is funny and has an unusual twist, I can really recommend to watch it.
What I didn't understand was that although this was the second day the film was watchable in our cinemas, the hall where we watched it was completely empty. We were the only ones in that cinema yesterday. Felt very weired, and in the beginning we thought we might be in the wrong room. Is it because the film is not that known? Is it because they already launched in the USA in March and all people already watched the downloaded version? Strange.