It's not all Spongebob's fault!

Nutrition experts have determined based on a number of studies that parents are primarily responsible for rising childhood obesity rates. But what about the consenus that Spongebob, McDonald's and Oreos were responsible? Is this not all the fault of greedy corporate executives? Are these experts actually saying that the people who buy the food for the children may be the culprit? Do adults actually have the power to tell a 6 year-old no when they want soda for breakfast? Is it possible that there is a level of personal responsibility involved?