Then those "not needed" will rationally (and in many instance literally) kick those rational consumers in the head, in order to have something to put on the table. It's as simple as that. And then it becomes a race of "let's better fund the police so that we'll keep the not needed at bay" vs "maybe it's just not good policy to kick the not needed while they're down, maybe it's not all their fault".
We should be expecting a smaller proportion of the population to be working in most sub-sectors of the economy each year, as new, innovative areas provide opportunities for relatively inexperienced people with high aptitude to work more productively and earn higher wages. It's fine having people bagging groceries at supermarket checkouts, but that isn't really going to work out in the coming years if those same people are going to be demanding state-of-the-art medical treatments, developed-world retirement benefits and cutting-edge consumer goods.
