The difference here isn't between "models"... It is, actually. It's a different economic model (ie, formula) to express demand solely as a function of profitab

The difference here isn't between "models"... It is, actually. It's a different economic model (ie, formula) to express demand solely as a function of profitability than it is to describe it as driven by what someone is willing to pay, one possible factor in which is their profit motive. The reality is that we pay for things all the time without regard to their profitability. The fact that for-profit schools exist does not mean that there is no other valid rationale for paying teachers besides profit.