All the time.
We have a series here at our local theatre called Sneak Peek.
You never know what movie they will play, just that it's a premier and undubbed (Germany here).
So I end up seeing a whole lot of movies I've never seen trailers or other promotional stuff or even heard of before.
There are a few stinkers in there but also a lot of at least good movies I'd never would have picked deliberately. So that balances out I guess.