Bombay Duck

Bombay Duck was originally pronounced as Bombay Daak (Bombay Mail in English)…when it used to arrive in Calcutta for the Viceroy all the way from Bombay via train…

Loutey machh (Bombay Duck) in the making…why is Bombay Duck double the price we pay in Kolkata when we buy em in Bombay? Actually it is 4 times costlier! Strange!