A moderator on the Nintendo Forum has posted the following: “You are not permitted to share your NWC id or friend code on a post, in your profile, through PM, or in a sig. Please do not discuss other ways of sharing codes either. This policy was created by Nintendo of America and we have been asked to follow these rules.”
That doesn’t make much sense. Why have a unique ID number, if they discourage its use. Granted, this may be to protect and child’s identity, but last I checked you can’t chat in Mario Kart or communicate in any other way besides racing. Right?