All eggshells are white as they cruise through the oviduct. So why are some eggshells different colors?

Seems to me the Easter Bunny is going to be out of a job soon... Different breeds produce their own dye to be applied to the eggshell. While the eggshell is being dyed, the egg is rotating.

With the addition of the fall chicks, an entire rainbow of eggs will be falling out of Cluckingham Palace. Peach ones, white ones, chocolate ones, olive green ones, blue green ones, brown speckled ones...