I DO NOT answer phone unless I recognize number. My ans. machine is NEVER on. Friends/relatives know my cell. If I answer then YES, they will sell the number. I keep a LIST beside my phone with these numbers and when a new number comes in, I find it n call notes. This has cut down on many, many calls because I DO NOT ANSWER.
What exactly do you think the DNC is supposed to do? It's not a call blocker so it can't keep scammers from calling you and they certainly aren't going to follow it. You might want to invest in an actual call blocker, though.