Frango mints are probably the best example of the Chicago affliction of being attached to long-gone Chicago stores and products.
Although "Frangos were created by Seattle, Washington's Frederick & Nelson department store in 1918; the company and Frango trademarks were both acquired by Chicago's Marshall Field's department store, which introduced its recipe in 1929.[2] For many years, Frango mints were produced in large melting pots on the 13th floor of the flagship Marshall Field's store on State Street.[3]" [from Wikipedia]
They're one of these Chicago products that tourists would buy as souvenirs and that your mother might bring as a gift when making an annual pilgrimage to visit cousins in Michigan.
People are still basically crushed that Macy's now makes Frangos, even though it's been HOW MANY YEARS. Read this and see exactly what it means that Chicagoans are really, really attached to their long-gone stores and products.