This case sounded so stupid to me that at first I thought it had to be a joke, but here's the actual ruling, Sugawara v. PepsiCo, Inc., so apparently it's true.
Janine Sugawara filed suit against PepsiCo, maker of Cap'n Crunch's CrunchBerries, alleging she had been deceived by their marketing into believing that crunchberries were real fruit, only to learn, to her dismay, that the product contained "no berries of any kind."
The judge threw the case out, noting, "The survival of the instant claim would require this Court to ignore all concepts of personal responsibility and common sense."
Sugawara is a serial litigant (pun intended). She had previously filed suit against the maker of Froot Loops for similar reasons. Link: Lowering the Bar