For multi-entry rooms (many rooms that aren't bedrooms or bathrooms, and even occasionally bedrooms and bathrooms) this is often true of less than all the entrances to the room.
> Once you're inside, you rarely have to touch them again until you exit.
Not all that true if you are in a room with substantial natural light across the day/night transition.
> Don't get me started on the motion sensing lights TFA mentions. I curse the times I've entered a public bathroom that has these, only for the light to go off at the most inopportune moment. Don't want to use a physical switch because of sanitation? That's fine, but cheap and low-power LED lights exist for them to be always on during your service hours. You won't save much having the light turn off, and potentially annoy your customers.
Motion sensing lights with sensors designed to track motion outside of the stalls and a short timer exist specifically to "annoy your customers". Or. more specifically, they exist to discourage activities that involve spending an extended time in the stalls, whether it is various uncouth activities or merely employee malingering. Obviously, that also has adverse impacts on people doing normal bathroom activities that happen to take longer than average times, but that's a tradeoff the people employing these systems have decided is worthwhile.
It is not about energy savings, so arguing against it as unnecessary for energy savings misses the point.