I don't think groups need that at all. There's nothing the group has to gain from it or give back for it. Llamas were made to give people an introduction to the Points system while being a fun way to get individual members to meet other artists. A group, however, kinda already serves that second function and is easier to find.
Just a short thing.
It would be nice if you could give badges like the Llama to groups like to normal people.
Now you have no "give" option... you have to put "/badges/" after the group-url and then go on the llama-option. No one finds this way to give them...
Greatings!