Chapter 12 illustrates that cheating exists at all levels of business, from the owners and workers in the big companies to the young boys selling papers. Capitalism and cheating exist hand in hand.
Jonas' disappearance can be accounted for in one of two ways. He may be a victim of an industrial accident and subsequent cover-up, or he may, in all likelihood, have just left. In Packingtown, having a family is a curse, not a blessing, and Jonas can find more success on his own, so it is more quite possible that Jonas abandoned his family.
In addition to having been injured on the job, Jurgis is no longer the brawny young man he once was, and the industry that weakened and practically destroyed him no longer wants him. Jurgis searches in vain for any sort of employment, but he is no longer a viable candidate.
