As a French the lack of "volet" (these white shutters) in other countries drives me mad. How can you sleep in a bedroom that is not totally dark after sunset? At least here in Japan they have these anti-typhoon metal shutters that I can use...
Personally, I can sleep if it's not completely dark (although it's way better if it is). What I can't stand is if there is no fresh airflow, which closing these shutters also blocks. But I am in general extremely angry at the amount of light polution everywhere, too.
