You mean (for an AWS S3 backed system): trust your privacy to an application binary (or, potentially, source which might get audited periodically, and that the toolchain and binary correspond to that...), plus to any OS or application bugs at other layers...

Being able to work on a totally disconnected network is different. Maybe if you could support Eucalyptus's S3 or another backing store like that it would be equivalent (and that might be interesting).

I'm sure plenty of people are fine with an Internet-connected, AWS S3 backed system, though, especially with additional crypto.