Hidden profits, hidden rents

"In general, only accounting profit is measured while only economic profit is interesting. When we think of economic profit, we need not restrict ourselves to shareholders, who represent just one class of claimants on an enterprise. Suppose there is an industry whose firms about break even in accounting terms, but whose unionized workers, even those without hard-to-find skills, capture salaries much larger than they likely would outside of the industry. Is the industry “profitable”?
In an economic sense, it is very profitable. It generates sales that far exceed the opportunity cost of its inputs. But for institutional reasons, those profits are captured by workers rather than accruing to equityholders, and so are missed by accounting measures. It’s pretty clear that, in its heyday, the US auto industry was like this. The industry generated a great deal more “value” than was captured by its shareholders. The internal negotiations between firm stakeholders over the distribution of economic profit has no bearing on the existence of that profit."