Lately with people who ask me for free gifts. I ask them to listen to me rant about politics, wait them to respond and continue.
As second way of making sure the person won't come back nor (her) friends. Is to ask and wonder how much impact a one eyed beaver has to gasoline prices. Thinking, he can't see so well, eats the wrong tree, power line falls down. Wire hits a truck, truck hits a moose. Dying moose attracts bear witch follows a hunter, bullet misses the target. Hit's Vladimir's car, driver gets scared. Drives to a ditch. This is act of war and so on
soon enough, you have no one bothering you anymore.
Third way.. (my favorite)
https://www.youtube.com/watch?v=tVj0ZTS4WF4 ask them to watch that and start a discussion about the song.