God, I wish I could remember the name of the comedian who told this joke but it's been so long since I saw him perform it on TV that I truly have no idea. However, I do remember the basics of the joke and why it has stuck with me all these years. To paraphrase:
The comedian was doing a show in the deep south and decided to go to one of those waffle houses they seem to love so much for breakfast. The "waffle waitress" as he referred to her took his order and he started reading a book he'd brought.
"Lookit him," someone in he restaurant said. "He's got him a book!"
Someone else stood up, hands on hips, and said, "Looks like we got us a reader."
Baffled, the comedian gazed about the room as the waffle waitress returned with his coffee and stared at him with squinty eyes. "What'choo readin' a book fer?" she asked.
The comedian shrugged. "I don't know...so I won't have to become a waffle waitress!"