Earlier this year, there was a successful campaign to restore the vegetarian status of the Mars Bar. The campaign apparently benefited both Mars consumers and the company itself. (See my posts Life on Mars, 2, 3.)
Now it's Cadbury's turn. "Facebook Campaign Saves Departed Candy Bar" (WebProNews via Scribe).
In similar vein, I recall a brilliant marketing anti-campaign when I was a child - people had bumper stickers attacking the Esso Marketing Manager, and demanding the return of the Esso Tiger. (This was decades before the environmentalists started to demand the Tiger Out of Your Tank.)
In my more cynical moments, I imagine the possibility that these campaigns might be orchestrated by the companies themselves. But of course from a POSIWID perspective, it may be unclear and maybe even unimportant who is manipulating whom. A wise company always allows itself to be influenced by its customers - so who is really in charge?