Earlier quoted context omitted.
Credit cards give me cashback, worldwide acceptance and peace of mind. The country I live in, Switzerland, has a very widely accepted QR-based payment system... but credit cards (in mobile wallets) are more convenient, safer, faster. The only time I use the QR codes is when a merchant doesn't have a card terminal.
The cashback you are given back is taken from a fraction of the fee levied on merchants by the Payment Processing company they use. The only thing holding this system together is the lobby (also funded by a part of the aforementioned fee on merchants) by the Payment Processing industry to uphold laws that prohibit more expensive payments for more expensive payment methods, and also the extensive marketing (funded by…
Merchants have a psychological (and in some countries, legal) barrier to charging more for cash than other payment methods, even though it's the least efficient. Given this, cash-back is the best way to share the efficiency gains with the end user. Maybe if Pix or Twint or debit cards or what-have-you are so efficient, they should also give consumers cashback.