If you're looking for a place where nearly every restaurant is a great one, the island of St. Simon's Island, Georgia is for you. My favorite casual breakfast spot, as everyone has their own, is Sweet Mama's, which has changed locations at least three times since I've been going there.
Sweet Mama's is where I carb load for a long day at the beach by ordering a sausage biscuit and a pork pop, a pastry filled with bacon. Their sweets, as the name implies, aren't bad either, especially the brownies, pound cake bar, cheese Danishes and massive chocolate chip cookies. All are under $5, so go wild.
It's only open for breakfast and lunch Monday through Saturday, so you may have to stock up to get you through the rest of the day. Sweet Mama's is currently located in an unassuming strip mall and therefore easy to miss, but look out for the Winn Dixie.