NFC is very much used in other places like Europe. I just got back from a trip to the UK and Iceland where I used contactless payments almost exclusively (except for automated gas pumps which required chip-and-PIN). I don’t remember seeing many QR codes at all.
With contactless payments, you share your payment information with the point of sales. You do not get the opportunity to check what's going on (and it will never be due to the awkward position you have to hold your phone to get within NFC range).
For QR code payments, the point of sales generates all the information (how much money to which merchant) and encodes it at QR. You scan the code and confirm the information, which results in a payment.
