China does have some car brands that support battery swapping, with NIO being a notable example that markets this feature. However, their market share isn’t particularly high. It can be said that battery swapping is a common practice in China, but it isn’t the primary method for electric vehicle energy replenishment. Incidentally, NIO vehicles don’t support particularly high charging speeds. High-speed charging can impact battery lifespan, so manufacturers like NIO also prefer to avoid promoting fast charging from their perspective.
> It seemed difficult (impossible?) to pay with anything but cash
That's true and it is not convenient for visitors. Local people usually just use public transportation card (magnetic/contact-less smart card) everyday and don't have to pay with cash (you can charge the card with credit card or Alipay). Some station gates also support paying with NFC smartphones (eg. Xiaomi), and I think that's modern :-)
You get 192 -> 100 bytes reduction if there's only one response. The compression dictionary(dynamic table) is shared, therefore much more bytes can be saved in the following responses(assuming they contain similar headers).
No surprise for me. ISPs in China even rewrite your web pages and inject their own Ads. The only way to stop this is keeping dialing the customer hotline and shouting at the custom service. Yes, this does work.