#1 majority hashpower is in China. Chinese mines can be controlled or shut down by the People's Bank or the government.
If the chinese can produce something domestically, they do.
Why "import" BTCs for dollars, from foreign miners, when they can produce them locally?
If Chinese production of BTCs can satisfy local BTC hunger (prevents USD outflows) or even be used for "export" (USD inflows), then it's a "profitable" activity for their economy.