[rdouble]

In this particular story the answers are easy.

The work of a steveadore, one of the examples given, has been vastly automated and unionized. The work is much physically easier than before: operating a crane vs. manually moving cargo. Dockworker's unions have negotiated strong agreements related to overtime pay which guarantee time and a half. There are a far smaller number of employees needed, and those employees want to pack in as many hours as they legally can, to reap the overtime benefits. Automation of an industry can actually lead to longer hours for the fewer employees still working in the industry.

Since there are far fewer well paying positions like being a longshoreman, people who may have once gotten a job on the docks have to compete with everyone else for service jobs. The service jobs don't pay enough, so many need 2 or even 3 jobs to keep their families afloat. The need for multiple jobs explains why this class of people is working longer.