Asian culture is not that much about sharing as about obligation - toward parents, other family members, etc. Latin culture is more about sharing.
It is a difficult problem, and one you will not solve unless your wife is on board. She is actually the one legitimate enough (at least in their eyes) to complain, and even in that case it will not pass well.
A potential solution would be to make your guests be more active: ask them to participate ("please clean the dishes while I clean your room", etc.). Be explicit, avoiding potential misunderstandings. Set clear rules and enforce them. It's a bit like educating animals, they might not "learn", but they will end up acquiring the habits, which is what you want - Pavlov anyone?
If they really do not learn, start making excuses. You have appointments, friends over, weekends away... Which makes it difficult (read "impossible") to have them over. They will slowly get the message. After all, the culture of hospitality only goes so far.
Oh... Eye for an eye is never good politics, specially with family in law.
Anyway... Whatever you do, you will get flak from the family, and that's why it is key to have your SO on your side, so brace yourselves. And, as another poster said, keep your objective in mind. It is not to be right, to receive a fair treatment or for the others to change and get more civilized. It is for you and your wife not to be invaded in your own house.
Good luck.