Never thought about all the celebs doing milk ads, and a relation to milk cartons being used to 'raise awareness' for missing kids.
One thing that did come to mind and I wonder if it's part of their 'symbolism', or just a marketing gimmick:
I was always creeped out by tv ads that end with the company slogan being whispered by a child. I know there are smany examples but can't happen to think of any at this moment, if anyone else can.