Vidiot: Suspiciously?
This. The WTS is concerned that college will lead young people astray. Keep in mind that JW parents are taught to monitor and manage their children to keep them safe from spiritual dangers. Once they head off to college, it is almost impossible to keep a close eye on them. Plus, they may learn things that don't come from the nutcases and quacks that the WTS often quotes from in their literature. Worst of all, they might learn about evolution!
Better to get a low-grade job that pays barely enough to keep a roof over their heads. Then the WTS can gripe about how little they contribute financially during tough times.