Apple Supports Slavery!
No, Apple does not. Every worker in Apple's supply chain is an employee who applied to work there. Assembly workers at FoxConn for example have queued by the thousands for every single opening on Apple's assembly line because it PAYS BETTER, by two to three times, than assembly work on other consumer electronics companies such as Microsoft's, Sony's, Lenovo's, HP's, etc, because Apple's contracts with FoxConn requires that level of pay for their workers on Apple's assembly lines. Apple's contracts also limits the number of hours of overtime and regulates working conditions. Apple is the ONLY CE company that puts its own full-time company employees into the plants to monitor the pay, working conditions, and overtime of the Contractors' employees doing Apple's work. The others merely pay money to non-profit watchdog groups.
Slaves don't apply do be slaves and slaves certainly don't get to quit if they don't like the working conditions.