"Something important came up, I have to go. "

[Sheer]

It's the fact that they can just stand there and do nothing and not be punished for it. Sure, you can kick them but odds are no ones going to be joining that instance any time soon(and they didn't.) I waited over 40 minutes just to get in and it's over before we even reached 15.

Well, they added the vote-to-kick feature for this exact reason. A lack of players queuing for the duty is nobody's fault. You can try reporting them for inappropriate conduct, but I can't see it getting too far. Perhaps a slap on the wrists?

[Tyrial]

Well, they added the vote-to-kick feature for this exact reason.

No, they added the Vote Kick feature to give parties an avenue of dealing with a player hell bent on harassing the party or for situations where somebody did go afk randomly. From what was said this person just didn't want to eat a penalty. That is NOT what the vote kick is for. As Paradine said, if it's that important just leave. This person just wanted a free kick so as not to have to eat the lock out timer for abandoning a duty.