Why are the cabin crew only allowed to use these bunks on sectors of over so many hours even when it is night and most of the passengers are sleeping? For example the DXB-JNB B777 route.
Haven't you forgotten something? Something quite fundamental?
Cabin crew are aboard the plane to
work; they are there for safety reasons and to cater to passengers' (reasonable) needs.
How can they achieve this if all they want to do is to get their heads down and to compete in the snoring stakes as soon as they possibly can?
Or is it a case of s*d the passengers: they are an occupational nuisance to the cabin crew, and therefore they can wait until some sleeping beauty of a cabin attendant deigns to wake up?