I can't speak for ya'all, but my email stays stored on my IMAP server on my personal box. If somebody wants my email, they'll have to get it from me. All of my mail filtering rules work on the server side, and I get a consistent view of my inbox and folders from all of my IMAP clients.

The thought that software is groveling my email in order to send targeted advertisements to me I find repugnant. Perhaps it's because I formed my ideas about how the Internet should work before it was commercialized.

No, but we should assume that someone working at the company where our mail is hosted could look at it. And more important, we should assume that the recipient could publish it someday.