The fact of the matter is that NOTHING prevents anybody from doing exactly the same which is buying Apple hardware and reselling it with AmigaOS provided the hardware is certified by Amiga (which should not pose a problem).
Why should I as a customer have to care about whether Amiga Inc. or anyone else ("Seehund GmbH") has signed any deals with Apple? Why should I not be able to buy my hardware from any of the (thousands, in the Apple case) dealers I prefer and install AmigaOS myself. Sure, I might choose a bundled system from "Seehund Inc." if their offer appeals to me as an individual customer, but I'd hate to see Seehund or other hypothetical VARs (although who would choose to compete over such a restricted market?) being the only available options...
As a personal note I would like to add that Apple hardware is so clearly branded "Apple" (typical Apple design etc.) that I as an Amiga user would not take any particular pleasure in running AmigaOS on a desktop machine when a valid alternative in the form of the AmigaOne is available.
You totally lost me now. You mean that the trademark the hardware is distributed under would have any relevance to the customer? So we'll slap a boingball sticker over that little apple if it means so much, then it's just as much "Amiga" as any old POP-mobo. Or just throw the Mac mobo in your favourite case, paint the Mac tower black or WHATEVER! If someone licensed a Mac model, would it suddenly transform into a more "valid" alternative then? They're all PPC hardware and there are no reasons to why porting AmigaOS would be any particular problems. Luckily (until a SonyATInVidiaIBMMotorola kind of giant takes over) there will be no more "Amigas", and you if anyone should know that by now.
I don't know what to say if you're seriously suggesting this is an argument to restrict the number of available hardware options. You concentrate on making and selling YOUR product and let your customers worry about the trademarks and stickers of THEIR hardware. Then you'll see people buying your product.
Different customers have different needs, and if you want to sell as much as possible you must satisfy as many needs as possible. Most of your market are hardened, knowledgable geeks, comfortable with assembling hardware and installing software. A minority is not. It's easy to cater for both those categories.