The concept that everyone must have a "job" (that is, work for someone else for a wage) is deep in the psyche of both the ruling class and the majority, so both reinforce it through culture and propaganda. It's no different from how previous societies believed that Jews controlled the banks, or children got sick and died because they were suffocated in their sleep by witches. It's rank idiocy, but it's rank idiocy that almost everyone believes.
Regarding those theories about the Jews... what do you mean, previous societies? Lots of people today actually, really believe that the faults of capitalism come from Jewish finance.
Ever read The Emperor's New Clothes?