Was my leader wrong to do this?

[Runespider]

If your group joined an XP alliance knowing full well you were just there to leech others work and then leave so the new leader would have to fill the large void your group left then yes it's very rude. How can you not see that? You basically did nothing for them because now they have to relight the large group of replacing players.

If what you state was the norm XP would be impossible because nobody would bother to make lights, they would just leech an XP alliance and then dump it. Maybe I'm just not as thick skinned as some but as lazy as I can be I would not do this, it's incredibly rude.

If it's a prior arrangement then it should be stated in party for everyone to see, if I had to take over an XP alliance and 1/3 of the group did that I would be pretty annoyed too.