We don't see the entirety of the Batcave, and it's not 5' across, though. There's one thing not showing the parts of the spaceship where the toilet is; it's another to clearly show that there is no toilet.
But that wasn't really my point; it wasn't just the toilet I was raising, and like you say, that's explainable. It appears that these people are kept there for years at a time, and there's not so much as a blanket, a chair, or a book. Nothing. And this is done so casually to them - and even the prisoners seem to think it's perfectly normal!
I can't speak to what they expect; I can only speak to the fact that *I* noticed it and considered the implications. Maybe I'm the only one! I don't think I'm that special though.![]()
Which again, I think it partly due to the folks doing the visuals, that they just didn't think of it/wanted this small box to display the prisoner in, and didn't think about the logistics of actually keeping a person in there.
My wife is watching NCIS now, and I notice on that show, they re-use a jail cell over different episodes that clearly has a bed and a toilet, and is actually larger than real jail cells I bet. So somebody on THAT show has thought about it.