ricecake , 4 hours ago

In this case they’re employees of a “delivery service partner”.

It’s roughly the same thing, except instead of driving a semitruck, you’re hired as a contractor to hire and manage the delivery drivers, do everything Amazon tells you, and make sure your drivers do everything Amazon tells them as well.
That way Amazon can pressure you into abusing the driver’s and claim it wasn’t them, it’s just that they hire terrible contractors. Refuse to negotiate because they don’t work for them.

Which, quite clearly, isn’t a thing you’re allowed to do, since even if your employees get their checks from someone else they’re still your employees since all the work they do is for you.