I did try to search for something on this topic but came up unsuccessful. I recently came across a user with quite a bit of negative reputation and looked at the details for them. One of the -4's he had, had the reason "just joining the club". This is definitely not right and should be fixed, if the user that gave the rep doesn't have a reason for it, then why give him a -4? Because you want to join in on all the bad reputation the user is getting?
This may not be against the rules, I'm not sure. If there is something that talks about this, please link me to it.