Yup and that's the issue with turtle but that's another topic.
Just give up like me. People here don't want any form of punishment for leaving a group. They want to be able to leave any group they like, how many times they want in a day with no punishment, they don't care about 4 other's time. They want to leave for any reason even if it is a silly one. Heck I even suggest just showing them how many keys they left in a week and it gets reset weekly and that was still too much punishment for them. Just give up and move on. People simply want to be waste otherrs time by leaving. Nothing you can do unit blizzard actually start handling out punishment with like solo shuffle in PvP.