The idea of the Dongle seems simple to me.
Amiga Inc. need a computer hardware platform, so they promise Eyetech that the new OS will only run on the AmigaOne, i.e. the machine EyeTech are building. They do this by requiring a Dongle. Eyetech are happy as they know that they will sell a few computers, Amiga Inc. are happy becuase they have some new hardware to call Amiga.
Once both the companies have got their products out, I don't believe for a moment that Amiga Inc. will keep the Dongle requirement in, or at least they will be flexible as to how they licence the OS.
This is the only way I can understand the current business model, it simply doesn't work any other way.
This Dongle is simply a way of making sure both companies can cover their costs, to set the ball rolling so to speak. Once the ball is rolling we may well see a lot of changes.
These are just my (wrong?) opinions and not those of any groups or organisations I may be connect with.