You're not forced to use smartphones. I happen to live in China, and there are people without them.
You can buy tickets at the counter or vending machines, you can text or call instead of sending wechat messages, you can pay bills by card or direct debit, and supermarkets all accept cards (Chinese ones, that is) or cash.
People use wechat or alipay out of convenience. Just like people in the West use whatsapp, signal, fb messenger, telegram or whatever else there is. And some of those are testing payment service integrations (whatsapp pay for example is live in India since a few months ago).
You don't like it - don't use it. Nobody will force you. But if it takes me 7 seconds on my phone to finish a task vs. 2h in person, guess which one I'm choosing.
Edit: Typo