I would be pretty surprised if Amazon insures their package delivery. Do you have a source for them using insurance?

Maybe when they use a 3rd party delivery service they can strongarm that service into eating the loss. But, where I am, Amazon is usually doing 1st party delivery.

(the reason I assume they don't is that a) they are big enough to eat any loss and b) losses happen at a pretty constant rate. So they would basically be paying an insurer $loss_amount * (1+insurer_margin) in premiums to immediately get payed back $loss_amount. not a great deal.)