You are right a7a7... I think they would do better by devalueing diggs from 'spammy' members. I believe they could do this covertly and no one would be the wiser.
An interesting topic, I understand where they are coming from but understand as well that their are perpetrators out there who will continue to make fake diggs to get known. Once the are blocked, use another account, and the problem will only escalate to a place where it will just be....fake.
may be digg should auto bury the story they submitted so after a few story they feel it is a waste of time and give up
They are. This was their official response for sites like subvertandprofit.com. "We figure it out, but we don't ban the users. We just make their diggs seem insignificant"