I don't get why you are all going off at the people who have said they don't have time for full dungeons, as they are not the ones abusing the system. The people without time will queue up for an in-progress while doing other stuff. Then if they get one, great. If they don't, they'll just log off as intended.

The people abusing it are the people who do have the time to sit there withdrawing over and over until they get a 2/3 progress pop. It is also more of a job specific problem than universal too. If a Tank/Healer withdraws, they have a good chance of getting another party instantly. If a DPS does it, back of the queue you go.