Chicks are commonly shipped from place to place due to a neat little design in chicken anatomy and physiology. When chicks hatch, the yolk is absorbed into their bellies as a reservoir that will last three days or so. This is important because a clutch of eggs under a momma hen will take 2-3 days for all to hatch. If the first few chicks did not have food in their tumtums they would die of starvation before the last eggs were hatched. Because of this, hatcheries can ship day old chicks across this great land of ours and have the babies at your local USPS for you to pick up. Then you get them home and give them food and water as their yolk has been used up and they need to be fed now.