Has anyone else noticed all the dairies/bakeries around the Auckland area, who are selling the Coke range of cans which all state "not for individual sale" on them?

I find this quite amusing. Are their any specific laws regarding this issue? Can coke actually enforce any legal actions on these small businesses who sell these products which can?t be sold individually?

I?m guess they just purchase them from the supermarket because they are cheaper than purchasing them directly from the suppliers, but is it legal?