[seanmcdirmid]

We are talking about mountain people in Guizhou or Jiangxi though. These people are likely to still be fairly rustic and traditional, they aren't worried about Internet so much.

> That's probably why migrant workers often leave their kids with grandma.

Not really the main reason. Without Hukou, their kids can't even attend school. China is almost a caste-based society these days, where caste is determined by your Hukou.