You still have a Single Point of Failure. ChargeBee could shut you down too. You are right that redundancy is important, but redundancy either in cloud vendors

You still have a Single Point of Failure. ChargeBee could shut you down too. You are right that redundancy is important, but redundancy either in cloud vendors , payment processors or even high availability of your app takes time and effort with no immediate ROI as apposed to buliding features , better customer service. When running a small business you always take lot of risks by cutting short processes large organisations will have. Judging which ones to take and which to mitigate is a not a easy skill, many times people get it wrong .