[vel0city]

IR motion/proximity sensors are not basically cameras. You can't get an actual image from them. They are essentially a single, unfocused pixel tuned to a wide angle with a narrow filter tuned to specific wavelengths. Some of them will have a few extra pixels to try and reject background motion, but still we're talking like 3 or 4 pixels for a whole scene.

[AStonesThrow]

Sure, you and I can "know this" intellectually, but the end result is that there are conscious machines lurking in every public restroom, and they await our presence, and upon our arrival they awaken and they spring to life and perform their service for the hu-man whose body temperature is somewhat normal.

So it matters not whether it's one pixel or 50 megapixels doing the work there, what matters is that everyone who attends a baseball game or eats at a restaurant is accustomed to a conscious machine that can "see" their buttcheeks well enough to know exactly when to activate the flusher without any pesky hu-man touching it.

And that there is electrical power and, probably, networking available in the restrooms so that the conscious machines can stay alive and discuss buttcheek sightings with one another and their mothership.

[vel0city]

If you'd hide your spy camera in the soap dispenser viewing angle you'd hide your camera anywhere. You could choose to only use manual cisterns and you'd still have to worry about cameras hiding to see your junk. Probably even moreso since you're really got something to hide tbh, Streisand effect and all.