I use the Commbank app and NFC to pay for stuff, but only if I realise I’ve left my wallet in the car because I don’t want to get in the situation where I end up going to a place without an RFID card reader. 99.9% of the time I will pay with my card.
It also seems a bit awkward to say “I’ll pay with my phone” (though I’d imagine with uptake this will change).