They might have a point. In the first flat I lived in, my bathroom had no windows, hence my extractor fan came on automatically every time you switched the light on. That in turn woke up the baby, therefore I used to pee in the dark.
Turning the light on wakes me up more, so I prefer to leave it off in order to maintain my level of sleepiness so that I can sink comfortably back into slumber on my return.