I think this will turn out to be another example of a big business not knowing what is in its own best interest and reflexively resisting anything new because they are afraid of change. (The prime example of such behavior is how the movie business fought the introduction of the VCR and how it turned out to be a boon to their business.) What are the odds that someone who takes the effort to put themselves on a do not call list would ever buy something from a telemarketer? I would guess it's just about zero for all practical purposes. So I suspect that by weeding out bad prospects, the telemarketers will have a much higher acceptance rate and now get nearly as many customers for much less the cost. This will result in a loss of jobs for the poor people who actually make the calls, but who can believe the DMA when they say they are concerned about that.