It doesn't change the dynamic for AWS. It doesn't change for many of us. But it does for example for a student who forgot to terminate a stack and suddenly can't afford rent/utilities/shopping until the charge is resolved. These are amounts which can really mess up people's lives for weeks.
At their revenue, don't care about 5K charge, they can send to collections / sell to 3rd party collections agencies.
They do care about keeping you happy as a customer since your employers will be swayed by their employees.
So the former is much more likely to succeed, the latter will just make you look like a scammer.
At larger sums - they will do much more rigorous checks to avoid issues.