The reason i suggested all 6 in retail case is also to save them money. Printing and making those white boxes probably costs them money.
How kind of you!
There's no win-win situation here. Offer them all at once, there are people who can't afford to drop that kind of cash in one fell swoop. Offer them staggered, you pay a little more or maybe you miss one.
Wouldn't it be nice if we could all just pay cash for a house when we buy one? Think about how much money you'd save in interest. But it's much more feasible to take out a loan and pay in increments, even if that means that you end up paying more than the purchase price of the house.
And whacko's probably right - no way are they going to make those white mailer boxes. They're going to invest as little funds as possible in these last figures.