I would just like to say that contactless chip cards are ubiquitous, do not require a battery, are more secure (no reliance on QR codes) and have been around for years in the West.
The "feature" of WeChat is that it can be used for almost anything. It is a cash successor more so that a card alternative. Anyone can print, display or scan a QR code. Doesn't matter if it is a store, a friend or a random person. Doesn't matter if it is in the physical world, on a website or in a chat. And it is easy to do. And almost everyone uses it.
Contactless cards only matches WeChat in the same way something like Apple Pay does.
The more secure analogy comparable in price would be solutions like Square and PayPal Here. Smartphones are ubiquitous.
As the other reply says too, any shop can set this up easily. I challenge you to take contactless payments in your home country, it's nothing like simply getting a qr payment and involves merchant banking.
I've seen tiny remote rural village stores that would never even imagine having a visa PoS terminal with big wechat payment signs out front.