Firstly, you don't know they aren't night stopping somewhere down route. Just because they may flight your flight and then the one after it, or the one before it, which may return to base, doesn't mean they won't then take another flight and overnight in another city where the aircraft has a night stop.
A crew may go, for example ZRH-LHR-ZRH-FCO-ZRH-LHR and stop in London for the night. They will then go LHR-ZRH-DME-ZRH-CDG-ZRH the next day and spend the night back at home.
Also, if the crew get stuck down route somewhere due to a technical fault or a long delay puts them out of hours then they need to have things with them to ensure they are able to stay in a hotel unexpectedly.
Also, pretty sure they need a change of uniform in case of any spills or tears and that is something which won't fit in to a handbag.
I will agree though, there is no need for their baggage to take up so much room in the cabin when most aircraft have separate hold locations for crew baggage. In my experience when cabin space is running out the first thing to go in the hold is crew bags.
Last edited by edi_local; 8th Jan 2013 at 19:13.