Believe it or not the cultural differences are far greater in China than the UAE. So you may be flying around the world but your wife and kids have to be in China which is a much bigger cultural shock than the Gulf. Except for Shanghai and Beijing the other metropolisis in China are not expat friendly.
As a result people leave their wife and kids at home, hence the desire for commuting contracts, but communiting is a whole other ball game and many would prefer to have their families with them which is ultimately much much easier in the Gulf than it is in China.
P.S. I am not Emirates management. Just being real here. I know that pilots are being treated like muck out here but China throws up a whole set of other issues.