They dont call them Chief Sandwich Dispensers for nothing!
Consider this as well.The 744 has bunks and those bunks will be used by the cabin crew regardless of length of flight eg. lhr-cairo.
What really smells is that they have the cheek to ask the pilots for the use of their bunks when they are 2 crew! And you are quite right,they will be off that aircraft as quick as saying jack s**t. They do not clean up the aircraft during the night either,it looks like a bomb site on arrival,unlike singapore airlines.