David, indeed code blocks as we call them here are
only for code. They do quite a few useful things.
- They highlight code syntax almost as Mathematica does
- You can copy code from posted code block back to Mathematica and it will work
But you are correct, if you look around, especially at the posts by Wolfram employees you will find that text never goes into code block unless it is a comment in (* ... *). Text is typed in a usual way and you can use rich text formatting that is done with help of other useful buttons in the editor.