I have used - "Oh my God I can't sleep, I'm claustrophobic and a nervous flyer. It's stops me from hyperventialting to see out the window." Complete tosh and we both knew it but not worth an argeument, besides crew often just b****r off for ages and are not seen again until brekkie. I DO keep it down if I see the sun is gonna be in people's eyes though, as you do neeed to sleep. Good luck !