Why do Talking Heads on TV News use the phrase "He Drank the Kool Aid" as a way to express the idea that someone is brainwashed? and not very bright... I have a totally different meaning...

Ken Kesey served "ELECTRIC KOOL AID" at his Acid Test Parties. That was a beverage laced with LSD 25... The Grateful Dead Played Music and Everyone had a MASS TRIP Together... 

TV NEWS PEOPLE Now are referring to the Mass Suicide with the Christian Preacher Jim Jones at Jonestown... Someone who is a Gullible FOOL would Participate in that Tragedy...