I'm from India, and this is my view from my personal experience and from what i've seen around here. Here, most families live as a joint family and children start living on their own after getting married.

In some cases, if the child is the only kid for his parents, they all live together always. The advantage is, it reduces cost expenditure, and you can save a lot in many ways, and if the parents are sick, their children take care of them instead of appointing a health care professional to take care of them. And in the same way parents help their kids in every way.

On the other hand, when living a life alone from away due to work, most the earnings are spent just on rent and other day to day expenses and there is nothing left to save for future.

So, it depends on the families situation. If parents and children support each other and live in the same house its great and economical.