Something is either missing or just isn't accurate in the OPs description. The likelihood of this happening is extremely remote at best but frankly IMO highly

Something is either missing or just isn't accurate in the OPs description. The likelihood of this happening is extremely remote at best but frankly IMO highly improbable period. I honestly don't believe this happened as described, but that isn't to say surprise bills don't exist on all the cloud providers. So I could see maybe the OP got a $500 bill unexpectedly, but most likely because someone found/stole an old account credential out of a public git repository (or similar) and the OP just didn't realize/know it. That makes a ton more sense and I have seen it happen quite a few times, it is an honest but costly mistake. If that is the case though, usually AWS is wiling to work with you if you just talk to them and are honest. So I am not saying the OP didn't necessarily get a surprise bill but maybe he/she is misunderstanding what happened or is just anti-AWS for whatever reason and is trying to make some point. I have been using AWS almost since the public release and I have had a few clients who hit hard times and didn't pay their AWS invoice timely over the years, a few more clients where things went from free to need to pay and they didn't. Each of them had services terminated after 30 to 60 days max, usually a smaller dollar amount AWS will let go for ~2 months but you will have received numerous emails from them first before they will terminate the account. Also, if you contact AWS and ask for a payment extension they are also usually pretty decent about it, but no, they wouldn't allow an unpaid instance to run for years. If by some chance this happened (highly doubt it) it could be a software error on AWS's side and raising it to AWS would likely result in them forgiving the bill and fixing the issue because they don't want to miss out of revenue either. My last soap box point, AWS is very clear you are responsible for the instance/service termination to avoid charges, so is Azure and GCP for that matter. They all are clear on how it works, you are responsible for reading the information and complying with the rules. IME all the cloud provides give you some latitude on payments though because if they were too aggressive with account suspensions/terminations they could get smacked for that as well, possibly even sued over lost revenue etc, so they have significant warnings/out reach which document their attempts too contact you and resolve it before they terminate to avoid that scenario.