I don't understand what do they get by disconnecting? Nothing as far as i know, so what is the point? And besides that, aren't you able to still continue in battle after a player disconnects, being its team AI controlled.
Before they changed the raid system, raid supporters would also be charged 50 stamina to enter the raids. So those who did DC abuse used to be raid supporters as well as raid room holders as they could still get the rewards without spending any stamina after having killed the dragon.
After they changed the raid system, ie. supporters wouldnt be charged any stamina to do raids, mainly raid room holders would be the DC abuse twats. This happens usually right on the bidding page after killing the dragon, and on your screen would pop up a floating message saying you got kicked out of the room, but the fact is the raid was completed and the rewards were being issued as shown on the bidding page, thus you ended up getting nothing, not even the raid points, on the other hand, the room holders, also the DC abuse twats, get all the rewards, gold, raid points and gears.
If those DC abuse kunts didnt get anything, those other players wouldnt be so annoyed like me.
In a few cases, this can also take place right before the dragon is nearly killed. And if you are fast enough to click off the game before the system deems the raid as a victory, that's ok, then no one can get any rewards. but most of the time you would not be fast enough to click screen off especially when there's no small dragon still alive and around with regards to r70+ or b60+
If DC takes in the middle of the raids, thats fine, because on your screen would pop a message saying room holder left and no rewards whatsoever, no one can take advantage of the DC either. this kind of DC also usually happens when the game is heavy loading as say 6 or 9 heroes spamming their skills at the same time. Over past few days I carried and helped other players with raids for more than 100 times and earned about 20m gold. I dont think it's hard to tell the difference between intentional DC abuse and innocent Disconnections.