If we're all quite through laying blame on "da gubmint" across a four year comment gap, let's look again at the lead comment from MJ.
WCA is the acronym for Worldwide Commerce Associates. Those who've been pelted by their calls *INVITED* them, even if unwittingly. This is a devious affiliate marketer which harvests both contact data AND consent to be pestered by any huckster willing to trade in sucker lists. Possibly call targets have filled in a survey or applied for a store discount card or inked some other seemingly innocent agreement which had WCA agreement language buried where one is meant to miss it.
The WCA problem is so bad they have an entire department and website devoted to ''compliance'' with demands for the calls and data mining to stop. Rather than rely on their ''opt-out'' mechanism, I would send a cease-comm notice via USPS Certified with return card, and demand that ''the buck stops here'' regarding the trade of personal data to total strangers.