Nonsense, AWS is an industry leader in use of the asterisk. With exception to perhaps S3 and AWS Lambda, the predominant majority of AWS services are cloaked with accounting legalese and hidden billing gotchas that can easily result in a several thousand dollar bill within days if you don't analyze every aspect of AWS service offerings including their EULAs and acceptable use policies.

So yes, it was bad form for OP to not establish billing alerts, but you can't in any way say that AWS is transparent about most aspects of their service tiers.