Darkened
rooms are also required for
amateur photo development,
sleep (for many
people) and the viewing of
glow-in-the-dark toys or
stick-on stars, activities which I suppose could be considered
sinister under the right circumstances, but generally probably aren't.
Yeah, I know that for photo development it isn't dark, just red, but it's funny how a color of light besides white or yellowish-white (those incandescent bulbs?) doesn't seem to make a room seem lit.