From the outside looking in, if your "last resort" comment truly was a guess to their reasoning, then I'm rather shocked. We're both on HN, so I have to assume we both work in tech and have access to the same information regarding why Amazon has earned its awful reputation.

Beyond that, I agree with your larger point, with an asterisk on "overpaying", as I do think an American company should have an incentive to prevent laying off workers just to refill them with offshoring and hiring H1Bs, especially at Amazon's scale of profitability.