Just received a robocall from them (on my cell phone) saying I'd won a free cruise to the Bahamas. All I had to do was participate in a survey. I'm not sure what kind of survey, either, as I hung up at that point; so I didn't get to hear who was behind it. I've been getting these calls more and more frequently on both my cell and my land line, even though both numbers are on the Do Not Call Registry lists.
BTW, what good are those registry lists if no one pays any attention to them?
The DNC works with legitimate companies because they "pay attention to it", as you say. The callers are scammers so they don't pay attention to the DNC. Perhaps invest in a call blocker or at the least, don't answer calls from numbers you don't recognise.