When they call, keep them on the line as long as possible (without giving them any pertinent info) They make money based off the number of successful calls they complete. If you tie them up on a never ending call it actually hurts them more than just hanging up (they just move to the next number) I usually try and talk to them about the weather, recipes, whatever random topics I can think of. Eventually they will get frustrated and hang up on you and quit calling, when they realize they are losing money and time by not getting anywhere with you. Then report their number to the National Do Not Call list.
I told her to never call back and she called me a degenerate gambler....she said she was returning my call so there was no intrusion on her part....they should be fined!