By that logic, _any_ company can effectively ignore the GPL constraints by just selling it to a reseller, first; one that they have a contract with to _not_ offer the source code when they re-sell it.

It is my understanding that, if I use GPL in my code, and I distribute it to someone that then re-distributes it to someone else... the GPL is still binding. I don't see why that wouldn't be the case with hardware using GPL'd software.