If not this, what exactly do they think financing is?

This is the entire fucking basis of their entire worldview. Actuarial data regarding ROIs and interest is the entire shtick. To them there should be nothing else that is important, nothing else should be considered sacred or important besides the APR generating a profit. Otherwise that's a compulsion to care about something and you would have to be like a jedi resisting the urge to be seduced by the dark side. Max ~~Steiner~~ Stirner would spit on your grave if you thought that this is anything but the most holy of civil interactions.