In our room on the Royal (interior cabin) there was one on the ceiling light between the bathroom and closet (picture) and one each at the base of the bedside tables to provide light when you step out of bed – but those floor sensors were too sensitive and it would light up even if you hung your foot over the edge of the bed. The only one that takes some thinking to block is the ceiling sensor, though. You can easily block the floor sensors with a shoe, pillow, etc.
If you want some light at night, you could either put a night light in the bathroom, or just leave the bathroom light on with the door closed – some light leaks out around the edges, but nothing too bright.