I understand too that the stripe, as shown in your next helmet example, indicates a touch up for the very reason you implied: paint scratched during "shipping and handling"! Interesting too- what do you think about the notion that changes in paint like your helmet, whether intentional or not act as camoflouge?
While diving in Truk, I came across a ship's hold full of helmets, stacked together in the manner as you said. Later while diving another ship, I saw what appeared to be more stacks of helmets. When I swam over to get a better look inside, the dive master stopped me. Once back on board our dive boat he gave me the reason: they were not helmets, but rather mines! Yikes!!!