The workers paying the bribes mostly were from well outside the area where the factories were, including nearby countries.
Quote from Apple's Supplier Responsibility report (page 7)
http://images.apple.com/supplierresponsibility/pdf/Apple_SR_...
Limiting Recruitment Fees
Some of our suppliers work with third-party labor agencies to hire contract workers from countries such as the Philippines, Thailand, Indonesia, and Vietnam. These agencies, in turn, may work through multiple subagencies in the hiring country, the workers’ home country, and, in some cases, all the
way back to the workers’ home village. By the time the worker has paid all fees across these agencies, the total cost can equal many months’ wages, forcing workers into debt to gain employment.
Apple views recruitment fee overcharges as debt-bonded labor, or involuntary labor, which is strictly prohibited by our Code. We limit recruitment fees to the equivalent of one month’s net wages and require suppliers to reimburse
overpaid fees for all foreign contract workers in their facilities, including workers not assigned to Apple projects. To the best of our knowledge, Apple is the only company in the electronics industry that mandates reimbursement of excessive recruitment fees.
Apple forced companies to reimburse more than $3.4 million that year to foreign contract workers, fees of as much as "thousands of dollars per worker".