Any advantage to formula text? (vs rich text)

I would imagine it would be helpful if you didn't want the page to interpret and render text as HTML.

Let's say for instance you wanted to provide some HTML to the user that they could copy and paste elsewhere. If you wanted to do this with a rich text field, you'd have to wrap the HTML you wanted to show on the page in a code tag or replace less than, greater than, and ampersand with their HTML Entity Numbers.