Amazon is expected to be good sports and take the loss exactly because that is their business strategy. Their mission statement is something like, "we seek to become Earth's most customer centric company." If they didn't have a relaxed refund policy, they wouldn't have the reputation they currently enjoy.
Contrary to what you've said, they do have public trust: just in the form of "Amazon does right by the customer." It's trust, not morality, that forms these expectations.
For the trustworthy customers who are equally concerned about their reputation, they wouldn't dare "cheat the system" by exploiting a pricing glitch. For them, there is symmetry of expectations.
The asymmetry only happens for customers who do not care about their reputation for being trustworthy. This can go the other way as well: an unscrupulous company who takes advantage of naive and trusting customers.
And I am a loyal customer due to that strategy. I had a month in which I had to cancel my credit cards, and my AWS account went unpaid. I knew it would be an entire month before I could put another card on the account due to stupidity at my bank.
I called them up and the rep not only let the account continue to operate unpaid, he waived the payment for the month. I have never, ever seen such customer service. AWS might be expensive, it might have a clunky interface and IAM might be a pain in the ass. But I know that I can trust them to keep my business running no matter what.
Contrary to what you've said, they do have public trust: just in the form of "Amazon does right by the customer." It's trust, not morality, that forms these expectations.
For the trustworthy customers who are equally concerned about their reputation, they wouldn't dare "cheat the system" by exploiting a pricing glitch. For them, there is symmetry of expectations.
The asymmetry only happens for customers who do not care about their reputation for being trustworthy. This can go the other way as well: an unscrupulous company who takes advantage of naive and trusting customers.