It that case they could send the product in other regions and countries without worry.
Since transportation package do not returned to sender it should be cheap enough to include the price into product cost.
Currently we use polystyrene packages with accumulators of cold. The price of such package is near $1. It could keep temperature before 5C for 5-7 hours. Ideally it should cost not more than $1-3 with ability to keep temperature below 0C for 12-24h.