If a publicly-financed bridge contributes to business output and surplus value, what is the purpose of distinguishing those who built it from 'productive' labor?
More broadly, seems to me that financial crises or their absence depend no less on the finances of "non-productive" enterprises as of productive ones. Anything that generates profits can generate bankruptcy and ensuing social instability. So whyfore the surplus concept? This is elementary to you and others, I imagine, but it might be of some interest to the less theoretically experienced among us.
That aside, does a secretary in an advertising agency produce surplus for the owners? Retail clerk? Why not?
On a different note, I agree that the poverty rate leaves something to be desired, but its inadequacies have nothing to do with state of the debate on poverty, IMO. It could be five points lower or higher in every year and few consequences would ensue. On the other hand, the availability of a consensus measure -- even a bad one -- is quite important in policy debates. It stimulates discussion, and it provides an entry point for some kind of policy response.
mbs