Because there are over 200 competing 3d printing companies in China.

Because the owners want to get rich, not live as pensioners.

Why does anyone innovate? When I sell something I don't care if the dollars come from the end user or the subsidy, I just want more of them.

Because China is actually a capitalist free market economy not a communist one.

Chinese companies compete with eachother ferociously. And Chinese society itself is dog eat dog. Everyone wants to make money.