It shouldn't really. I mean, it's not like devices don't come with at least 3 or 4 unique IDs for different purposes. Just using one of those for the default password or adding a new ID shouldn't be that big of a task.
I know that this is how some of the router/modem combos from french DSL providers worked - the admin and WPA passwords are two seperate UUIDs printed on the device.
The gateways provided by the cable ISPs here in Western Canada tend to have unique passwords. It would be prudent on the part of the device manufacturer to just create a scheme for creating default passwords based on the unique serial that the device has and then just print labels for each and have the default ROM just sort it out upon it being powered up for the first time.
I know that this is how some of the router/modem combos from french DSL providers worked - the admin and WPA passwords are two seperate UUIDs printed on the device.