Nikon might want to sell their product, but they also do not want the purchasers to unnecessarily damage their equipment. From the number of 3rd party RF remote manufactures and lens manufacturers one might conclude that Nikon does not discourage 3rd party products. But Nikon does have a quality edge in what it sells, so the purchase option is up to the user. There are 2 companies that are marketing RF modules to convert the Nikon CLS Wireless control to RF so the control distance and interference issues have been greatly improved for the photographer.
When using a Nikon F and a Vivitar 285 on a hot shoe mount I received quite a jolt through the PC sync port.