> Conclusion: Digital Ocean is just for testing, playing around, not suitable for production.

I think that's always been the standard position most people take. DO, Linode, etc are for personal side projects, hosting community websites, forums etc. They are not for running a real business on. Some people do, sure but if hosting cost is really that big a portion of your total budget you probably don't have a real business model yet anyway.

I am of the impression that people rent cloud services because they can expense the cost to someone else or because of an inability to plan long term or a need of low latency.