What's the point of winning more than one battle in Arid Ruins?
all you said is right... from my experience (250k might) the only reason i play it its because there is bigger chance to have karmic rock I in the poll. I have never seen them wining 3battles, you will need to win at least 4... you may think 1 karmic rock... waste of time.. but it is possible to get more of them.(max i got is 3 in all 5 battles not bad if you are getting them every day.
And yes it is very annoying when players leave the battle... always better to fight with 'friend'