At $15/hr, what happens to the Wal-Mart greeter?

The pro-high-minimum wage line is generally that workers who are paid higher wages are more productive.  The logic is, of course, faulty, because they’re looking at employers who choose to pay their employees above-minimum wages for what are, in terms of the work required, unskilled jobs, to get more-productive workers, and extrapolating to a situation in which all employers are required to pay this wage as a baseline.

But let’s take it as a given that this will be the case — because employers will demand higher productivity from their workers, to produce the same output with fewer workers, or to exceed that threshold above which a human worker is still worth more than automation.  

What happens to those workers who simply can’t “step up” and meet these heightened expectations?

Teenagers, for one, and young adults who just don’t have those basic work-ethic type of skills, could probably be helped by a sub-minimum “training” wage.  Australia, that high-minimum-wage paradise, has exactly this:  a much lower minimum for teens (pardon my not looking this up right now).  

The disabled, of course, are accomodated, at various “sheltered workshop” places, by measuring their relative productivity compared to the non-disabled.  Perhaps ordinary workplaces hiring the disabled, such as grocery stores, might push to be able to pay similar sub-minimum wages.

And the elderly, who work at non-strenuous jobs to supplement their Social Security, who ask if I’d like a sales circular and Meijer’s, for instance?  Will they find these sorts of jobs closed to them?  Or will they also need a special category of subminimum wage?