Given the software that banks generally produce, it’d have to be a sufficiently good reward. If I’m buying a $10 sandwich at a deli counter, I’m going to double tap my power button and tap my phone on the debit machine. A $0.03 cash back isn’t worth the hassle to fish around to find my bank’s app, enter a secure password, and then enter a 2FA code. I had another comment elsewhere in this thread: want me to use the bank app instead of Apple Pay? Make the bank app suck less.