Your use of the term “morality” here seems to ignore that it is moral to honor contracts.

The contract between amazon and the customer is and should be asymmetrical.

One example is, as a customer, I can return most items for a complete refund within a time period. Amazon isn’t expected to come take my stuff back from my house if they aren’t happy.

One reason for that is the buyer and seller in this case have a massive information asymmetry such that commerce might be impossible without the contractual asymmetry.

This is enough to explain the difference in expectations without wandering too far philosophically.