You take on debts probably every day. Whether they are with your friends, family or future self. They don't necessarily need to be purely monetary but they are energy or time based.

We can have moral debts with friends and family which are a positive some game.

If you stay up all night posting news you will repay that sleep.

Maybe you're issue is with a very specific kind of situation where you do not know the source of the debt value being traded.