>as the consumer
This is where this discrepancy occurs. AWS (etc.) aren't targeting "consumers," they're targeting enterprises. Enterprises want to use these services with minimal interference and overhead. They'll build out whatever features they need as they need them. It's the same thing with any other utility service: a factory isn't interested in having the electric company or water company shut off their services if their usage spikes. They'll manage their usage (and potential overages) in whatever way is specifically suitable for them.
Consumers have plenty of options to prevent such situations. Hell, AWS even offers Lightsail which is the consumer-friendly version of their services which is designed to be simple with a flat rate cost (including options of object storage).
If a consumer decides to tap into enterprise-grade services and ends up getting burned as a result, then I'm blaming the consumer rather than the provider of those services. These dynamics are all pretty clear and easy to understand (and even mitigate, with enough effort), so I don't see how you can claim they are "opaque" unless you're the kind of consumer who feels every company should dumb down their products to cater to the lowest common denominator.