Them hippie dippie tree huggers never mentioned this.

Recently, a bunch of nerds from NASA and Penn State, came up with several different reasons as to why aliens from another planet might come to Earth. They range from good to bad. One is just a friendly, "Howdy Neighbor!" and another is total annihilation. One of the reasons they may beam down and kill us all is because of the way we're polluting the planet. It could change the chemical composition of Earth's atmosphere and therefor affect the Galaxy so they would have to step in for the greater good. Here's the point, next time you're done with your fast food and you want to throw it out the window, remember that anal probing is a real bitch.