One recent example: paying bills in Switzerland [1]. Although those have to be scanned by a banking app.
[1] https://www.six-group.com/en/newsroom/media-releases/2020/20...
[1] https://www.six-group.com/en/newsroom/media-releases/2020/20...
What is required is that you, when creating an invoice, provide the QR code for doing so.