From the post:
"Nikon USA has defended its decision to stop supplying spare parts to companies outside its authorized service network. Its intention is to deliver 'the best service experience to the customer,' says David Dentry, General Manager of Customer Relations at Nikon Inc, explaining that the complexity of modern cameras and the need for specialist analysis and calibration tools meant that repair attempts by ill-equipped retail or unauthorized repair shops could end up causing delays, increase the cost and risk voiding the camera's warranty."
If that's the case, then Nikon should still let the independent repair shops have access to ordinary parts. Those parts that does not require specialist analysis and calibration tools.
For example: Rubber grip, casing etc...