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.