Is there such a thing as a negative product placement?

Saw two movies today, "Idiocracy" and "Talladega Nights". I enjoyed them both immensely, very good comedies. As I watched though, something struck me. Although the two are very different films, they do have one thing in common: they both managed to fund themselves with negative product placements.

For example, in Idiocracy, a dystopian 2505 where the average IQ has dropped to rock bottom, Carl's Jr. now has the ability to take over the care and raising of children for customers who cannot pay their bill. In Talladega Nights, our hero's deadbeat dad tells him he has taped a bag of cocaine to the bottom of the car where in fact it is merely a bag of Lucky Charms.

Now, what I want to know is: does this really work? The Carl's Jr. ads where all over the place in Idiocracy, but in every single instance they were doing something negative. Everyone knows the expression that any publicity is good publicity but presenting your company as a facist organization seems to put paid to that bit of wisdom. And children's cereal instead of cocaine? Not eaten by the protaginist, but dumped on the ground in digust. It was a funny scene, and a good joke, but why would Lucky Charms pay to have their cereal, their product name be the butt of a joke?

Guess I just lack the skills to survive in the world of advertising.