The best example of a vocal minority that I can think of is when Rain (Bi, pronounced bee: 비 in Korean) won Time's 2007 online poll for the world's most influential person even though he wasn't even on the ballot. Most people in the world outside of southeast Asia had no idea who Bi was in 2007, let alone were influenced by him in any way. He most certainly was not the world's most influential person, but through the power of their Internet connections (and some bots I'm sure,) Koreans - the extremely vocal minority - made him so.
Bring on the fat shaming! I would like to see obesity receive the same vilification treatment that cigarettes have. Heart disease kills way more people than lung cancer. A woman lights up a cigarette next to her child and she's the disgusting spawn of satan. She brings that same child to McDonald's and no one bats an eyelash.