@Merry Andrew,
What's really befuddling is when say movies like
Planet 51 animated films don't even try to invent fake merchandise. In the trailer, one alien tries to decipher/translate the bar code on a really really generic bag of candy brand candy. They didn't need a product placement but couldn't they have used they're imagination and made a brand up?
In this case, it's just laziness that's the problem.