Don't forget, it's not like the ruthless megacorp has to pay those steep skillwire prices every time they hire a new employee. They need to pay for the skillwires (and skilljack, and skillsoft) once per position. When someone quits, is fired, or dies, they can yank the hardware (which is likely in their contract somewhere) and install it, used, in the next desperate employee to come of age (who doesn't have an "alpha-plus!" tier employment benefits package, or something).
The wires, jack, and softs stay in that office forever, if the corp wants them to. It's just the bodies that come and go.