Why don't email programs store their files in a more friendly format in My Documents like other programs?

Question

Why do email programs like Outlook and Thunderbird store emails the way they do in unfriendly formats in strange locations on my hard drive. What I mean is, why doesn't each program act more like word processors and create a Outlook (or) Thunderbird Emails folder in My Documents, with each email an individual clickable file that opens the program, and a folder structure that mirrors the folder tree found in each program?

We live in an era where photos are heading towards 10 megs so I don't think size is an issue. A lot of the needed info for for the special email features, threads ect, could embedded in the email and the program could extract it when started up.

Answer 1

Because of the options to view mail in threads, by history, by sender, etc., they are kept in a database like structure rather than in free form. You can export your folders to text files if you wish. Also, e-mail messages are almost always short (except for big pictures) and storing each one separately would waste a lot of space on the harddisk when a 1K message was stored in an 8K sector as files have to be.