Back in the so called "Golden Age of Porn" there were adult theaters almost everywhere. Even in small towns. Once the movie companies started building multiplexes out at the mall, the old, traditional movie houses were abandoned. So porn operators could buy or lease them cheaply and they became smut emporiums.
I learned pretty quickly that if you laid down an extra 10 dollar bill with the entry price, they weren't too quick to check your ID. By now the statute of limitations has long since expired, so I guess there's no harm in admitting that.
There was a theater in Virginia in mid 70's. Roanoke, I believe. They didn't show hardcore, but at that point in my development, seeing a real, almost-live, hair covered pussy on that huge screen was enough to make my hormones rage. I sat all the way through the two movies twice. My adolescent hormone-crazed brain even convinced me to go back for a second helping a day or so later.
My first visit was during the day and the only other patrons were "dirty old men" and other young guys who weren't working. The second stop was in the evening and the crowd was large, mostly male, of course. At some point though, a couple came in.
I found myself both surprised and a little embarrassed at the presence of a woman in the place. Then with a bit more reflection, I wondered what kind of a woman she must be to come to watch a sex movie in public. (Though in those days there was no way of watching one in private.) They sat across the aisle from me, a couple of seats in, with him to her left, putting him closer to me.