Heaven is high and the Emperor far away. Beijing doesn't and can't know everything in a country so vast and with so many people.But that is surely convenience and connivance.
That's why the central authorities (Imperial, Republican and Communist) put so much effort into finding out what's really going on when they find out something's going pear shaped - because otherwise they're reliant on local authorities.
It's also why the CCDI established their internet clipe-site, so that ordinary folk could bypass their local officials and report wrongdoing to Beijing. It's an internet-enabled upgrade to the traditional petition system.
It crashed repeatedly in the first week, due to the amount of traffic it received.