True enough, but you do get a bit more than just storage from tarsnap. S3 provides storage and an API for uploading things to it, but you can’t just back up your files to S3. You have to figure out what files have changed, compress them, encrypt them, and index them so you can retrieve them again later, etc, etc. That’s a non–trivial amount of software to write. It’d be really great if someone had already done so… Oh look, someone did!
I could imagine purchasing that software for a one–time price, running it myself, and paying AWS for storage. But then I’d have to monitor it, troubleshoot outages, maintain things, etc, etc. Or I could pay someone else to do all of that. I’m not currently a customer, but I know which I prefer.
