Clarification on new D2D material?

[SpacePhoenix]

I can't see d2d being an an envelope, even one designed to break open when posted through the letter, why would the companies sending d2d want there d2d put in an envelope with other companies d2d, also being in an envelope there would be a lot greater chance of the end customer (the person receiving the d2d and their usual mail) just binning the envelope full of d2d without even bothering to open it, none of the d2d would get seen at all. When it's loose, at least the person will have to have a look at it, even if it's a 1 second glance at it before they bin it.