this is 1/2 true... they are orange because they are free range, but not because they eat each others shit... it's because when they are allowed to free range they have access to grass/weeds. Eating green vegitation is what helps to make the yolks super rich in flavor and very orange in color...
I can't say that a chicken will never eat another chickens shit, but i have seen them stick their beak in a pile of shit and then immediately walk along dragging their beak on the ground like a guy wiping their fingers on the ground after they accidentally goldfinger themselves while taking a shit out hunting..... it's pretty comical really.....