The counterclaim which <em>Schlosser mentions</em> as a response to the argument is that:
Individual employers are often concerned about employees.
According to the given question, we are asked to state the counterclaim which <em>Schlosser mentions</em> as a response to the argument.
As a result of this, we can see that from the complete text, there is the argument which is made about the stance of the fast food industry and how <em>they care about their workers</em> to which Schlosser replied that the individual employers are not concerned about their workers.
