I used to get Slashdot sent to me as plain text. It was a sheer delight to read and I really miss having it formatted that way. I would pay a premium for it.

Maybe it is just that most people have never been exposed to properly formatted text emails?

I'm sure people find most of the websites they visit and the emails they read, filled with columns of extra garbage, to be cumbersome and difficult to read. Executives think that's what people want, but I doubt there has ever been an thorough examination of all the formats and their effects on people.