You're being more literal than I was. My point was that "a debt" is a broader concept than the GP comment acknowledges. A debt is incurred any time you propose or agree to buy something. And legal tender is the way you settle it.
But also, I think that most people would not consider any debt to be incurred for transactions where the payment and receipt of goods is done at the same time, like in a grocery store.
I was making a joke.
But also, I think that most people would not consider any debt to be incurred for transactions where the payment and receipt of goods is done at the same time, like in a grocery store.