Alcatraz. D-Block. Isolation. This shot two attempts and damn near half an hour to take, purely because of people wandering in from the entrance (to the left of the shot, not visible), seeing I was trying to get a shot, and continuing to aimlessly wander into frame. Same with the door at the other end, but not as bad. There was another photographer who came in and stood near where I was, we were both going for similar shots. Probably spent 15mins in silent recognition and empathy with one another as people would see us, both lining up and then having to drop camera as they meandered in the way. Eventually, a moment came, and the bursting sound of two cameras was over in a matter of seconds. We looked at each other, silently smiled and nodded, and parted ways.
Definitely a shot worth the time and effort, I think. It has a somewhat eerie feeling to it. People walking into your shots can be annoying, but I try not to blame the people. They probably have every right to be where they are and if I don't want them in my shot, then it's up to me to patiently wait. Also they're oftentimes just oblivious, or thinking "I'll just quickly pass by so the photographer can take a picture", or they don't want to awkwardly wait if they think you're going to be there for 5 minutes taking pictures.
Cheers, it was a pretty eerie place to be, especially entering the isolation cells and seeing what it would be like stuck inside. Not fun, is the least I can see. I agree with your point on people having the right to be somewhere, of course they do, and that applies for pretty much anywhere and everywhere. However, and without getting into a massive rant, common courtesy would be nice sometimes. If people don't see you, then that's fair enough; can't hold it against them for not knowing. It's frustrating when there are people who see you're lining up a shot, and then just continue walking into it. After waiting to take this, it was probably all over in 10-15 seconds. It's like taking a photo of a couple, and then having someone walk right between you and the couple as if it's no big deal. Anywho, photo was achieved, end rant haha.