Earlier quoted context omitted.
Who in the world uses debit cards
Setting your incredulity aside, I'm curious why you think using a debit card would be so shocking. I effectively don't use a credit card at all: I use a debit card (or an equivalent Apple Pay representation thereof) exclusively. From my perspective, if I want something and I have the money, I'll pay for it. If I want something and I don't have the money, I won't pay for it. I don't often want things outside my budget…
They make money off people who pay interest so I just take advantage of that.