Based in China. There are occasional times I'm unable to access HN without VPN. No idea if that's because it's being blocked or packets just aren't being given priority. Admittedly, China's pipes to the rest of the world are not very large.
Certainly they do. They use a machine learning DPI algorithm to block oversea VPNs and HTTPS/Socks proxys. So you can't hide your proxy in SSL or ssh tunnels.
Almost all foreigners has a vpn to access their facebook and gmail.
And for the demand, let me show you an example: Several months ago, a malware, XcodeGhost, infects EVERY large internet company in China. The attack worked by tricking developers into using a fake version of Xcode, Apple's software development tool, to build apps. So their apps were published to Apple App Store with hidden malicious code. This virus also has a android version. You may wonder why these developers didn't download the xcode and android sdk from apple and google's website directly. They are the top class developers in China. But the fact is they rarely use these websites and services. You can live without google even you are an android developer.