I think you need to move over to DU and not go telling FReepers what they "need" to do. As it happens I frequently mail disks in a 5x8 envelope with a piece of paperboard in there as a stiffener. The cost of this tripled with one of the recent penny increases. I really do not care whether my stuff doesn't go through the automated machinery. Maybe we could just through away all the automated machinery, cut the forced two minute conversations about whether I want to send my non-standard envelope by registered mail, whether I want delivery confirmation, whether I want to purchase any stamps, etc., and fire half of the postal workers starting with the ones who cannot speak English. (Or at my Post Office, the Box Mail attendant who is deaf and cannot hear the buzzer mounted next to the box mail window.)
ML/NJ
Tell you what, buy disk mailers that have the proper aspect ratio. You'll find that the costs go way down.
The lesson is that if you don't care if the mailpiece goes through the automation machinery then you'll have to pay the manual distribution rates ~ and let me tell you, it costs a whale of a lot more to sort mail by hand than with those machines.