Punish those who constantly quit Duty Finder

Every time I try to get into Crystal Tower, I get dozens of players quitting and making the system search for another player. People are doing this so they don't have to earn their gear by joining a duty that's already in progress so they can get the gear they desire.
It's not fair on the rest of us who run the whole thing as we have to wait longer to finally get 24 people, today it took me half an hour...
My idea is to temporary ban people from the duty finder for 30 minutes if they constantly quit more than three times or so.

Opinions?

Note: If you're going to say "I don't want to run the entire dungeon for a piece of gear" like I've heard before, that's the same as saying "why should I earn my gear?"

all they need to do is get rid of the Progress 0/1 that shows up. it shouldnt say anything and should be a gamble whether or not its in progress. You are already acknowledging that you are ok with going into a PiP by clicking the box so i dont know why they would keep that in there for sure.