Because courts are supposed to see through flimsy fictions like this. These companies are not in an ordinary vendor/customer relationship: they are controlled completely by Amazon, they do not and cannot serve customers other than Amazon, their conditions and working hours are set by Amazon, etc. They are Amazon subsidiaries in all but name, and their treatment by the law should reflect that.
Tell that to every government contractor. Many companies (that I'd wager you wouldn't take issue with) exist due to the contracts they have with a single government organization.
> Many companies (that I'd wager you wouldn't take issue with) exist due to the contracts they have with a single government organization.
But the government doesn't tell those companies "you cannot work for anyone but us." The government doesn't tell those companies "your employees must work these hours" (it may say "we require coverage for X period of time").
that kind of setup is actually fairly rare -- most of the work done in this sector is by large companies that have tens to hundreds of concurrent contracts from various government agencies. speaking from experience