people who have to work pretty hard for everything they have tend to be conservative in the literal sense of the term. middle class in china have a 50% of income savings rate or so I've heard.
I think the article got it right -- the "conservatives" simply feel they have more to lose. China's urban baby-boomer generation grew up during the Cultural Revolution in the '60s and '70s, where it was effectively mob rule by the Red Guards at a local level and many were sent to the countryside for re-education. They've seen what misguided "reform" can do and are not clamoring for it to happen again.