Our town had an x-rated drive in until the last ten years or so. It got raided every election cycle but it was always there. I dated a girl that loved to watch fuck movies and we'd go out there and sometimes double-dated. It didn't stop pervs from trying to cruise up quietly in their car and park beside you and wank themselves, hoping to flash someone.
As to theaters- I hate them. Since jeri-curl and all those other nasty, greasy hair products I won't rest my head agains headrests in public places like theaters or airplanes.
Watching a movie sitting upright is uncomfortable.