That's a false dicothomy. If the were not wasting their times on a unnecesary job, there is also a chance that they found a useful occupation.
And no it is not one. There is a big difference between "economically efficient" and "wasting their times on a unnecessary job", especially in the context of GMI.
You make it look that these two are the only alternatives when they are not (e.g. people could also be studying or actively searching for a job). Pretty much the definition of false dichotomy isn't it?