An ISO container can hold a lot of iPhones. You might notice however shipping terminals don't have a lot retail shoppers. There's in fact a whole chain of faci

An ISO container can hold a lot of iPhones. You might notice however shipping terminals don't have a lot retail shoppers. There's in fact a whole chain of facilities that handle supplies to retail outlets. Every gallon of diesel fuel burned to get things from those shipping terminals to a retailer emits about 20 pounds of CO2. Increasing the number of things per vehicle reduces each thing's CO2 contribution. It also decreases the shipping cost of each thing as it goes through that chain of supply. The shipping for each iPhone might be a small portion of its retail price but it needs to be paid up front and in aggregate. So millions of dollars in shipping costs getting even a 30% savings is still millions of dollars in savings. Besides the retail cost of goods is unrelated to the BOM and transaction costs. It's what the market will bear. Savings in BOM costs or transport just go into the retailer or manufacturer's pocket as profit.