Perhaps some cities hand out larger hongbao to the surveyors?

If people are grumpy about the "civilized KM" campaign, it is probably because said campaign made everyday life far, far, less convenient. Eg, fences at the subway stops making it nearly impossible to hail a taxi, or the near impossibilty of buying an er kuai.

Changchun? I know Cixi's hometown rather well. Apparently hot baijiu for breakfast counters frigid winters & dreadful air pollution!

Does The Guardian give references to professional journals? The popular press is notoriously unreliable when it comes to anything scientific or scholarly.

1100 years ago would 900s AD, well into the Iron Age. The early Bronze Age in Yunnan woukd be far older.