U.S. sales of the colorfully packaged morning staple have been in a decades-long decline, a trend back in the spotlight with news that Italian confectioner Ferrero Group plans to purchase the American company that makes Kellogg's Corn Flakes, Froot Loops, Rice Krispies and other familiar brands.

The transaction marks the end of Battle Creek's run as a quintessential company town in Michigan, where the name "Kellogg" graces almost everything.

The Italian maker of Ferrero Rocher and Nutella has set its sights on WK Kellogg as the U.S. cereal maker struggles to get traction.