[philipw]

I'm sure a significant contribution to this are NRI's purchasing from abroad where their earnings abroad give them greater power back home than in the local market. Whilst some people may rent out these properties thus serving that part of the market, others want to hang onto a new build / never lived in property. Some might say this is a form of insurance should they wish to move back, but its most likely just an investment that doesn't serve society.

And yes, this is very similar to investments made in London/New York/San Fran, but wealthy individuals trying to offshore their wealth, although these properties are typically rented out.