Except the fact that Amazon's office in Hyderabad India is the their largest in the world [1]. We are not talking about contractors - they are employees like any in their Seattle one, many actually do relocate back from US to India office.
I think the implication is that someone poorly paid and lightly supervised is more susceptible to bribery. Whether they are a contractor or full employee, or the color of their skin, is irrelevant. I personally doubt pay makes a difference, either you have integrity or you do not.
All in all, this is very embarrassing for Amazon.