Block merger/takeover, decreasing monopoly/oligopoly power.
Zero sum game is better than a negative sum game, right.......? Hedging........
I agree that buying a blocking stake would be the one instance where it isn't a zero sum game for them, but as I said in an earlier post, I really don't think that is their prime motivation.
I still think their main motivation is their view that resources companies are undervalued. So they figure if they get ripped off by paying for commodities, they can recoup this with high profits and share values on their share of resource companies that they hold.
You could label this a form of hedging.
I read somewhere today that in the next few decades 200 million Chinese peasants are expected to relocate to the cities. I personally think the number will be much higher than this.