This call is a robotic call claiming to be a contest. The way this scam work is that they will call randoms numbers and sew which one gets action (picked up or voice mail) once they know this is a live number they then sell it to scammers overseas so that they can try to do various scams on you. One of the ones they tried on me was calling and hanging up, if you return the call you are route and re-routed to a 1900 number. The number asks you to press 1 to be removed. you will then hear, "your number has been removed, thank you........ a $49.99 service fee will apply" most people hang up after the thank you and never hear that after the long pause you are being told that there is a huge fee for removing the number. this is a SCAM.
Your are correct. Those complaining the DNC list is useless fail to understand that legitimate companies do use the list. It's a list for law-abiding telemarketers to look at before calling someone. It is not some kind of computerized blocking tool that stops callers. So yes, if you do get a call like that it is from a criminal. Just like burglars can break into your house, these criminals will ignore the DNC list hoping to find someone to scam.
You are partially correct about overseas call centers. If the money trail leads to a US company using a foreign call center, the US company can be taken to the woodshed by the FTC. It is just often very difficult to find the trail leading back to a US company.