Oh come on. We all know that the 'accidental revenue' from the way Free Tier is set up probably makes up a cool 2 million or more annually. Plenty to justify its continued abuse of naive students. Why would they walk away from that cash? The only people they're pissing off is people who aren't using AWS anyway.
I’ve heard of plenty of people accidentally blasting past the free tier, or past dev credits, or other ways where they got burned by a surprise bill. 100% of those people have gotten a refund from AWS support by filing a ticket. AWS pretty clearly isn’t raking in money on this. Even at your imaginary 2 million a year, that’s a drop in the bucket for AWS, let alone Amazon.
I have a friend who I know didnt get a refund.
There is someone elsewhere in this post who didnt get a refund.
I don't know what the refund rate is, but it isn't 100%.