I remember a marketing professor talking about pet food labeling needing to be appealing not only to the humans buying it for pets but also for those who purchase it for human consumption. I offer the following from the Michigan State Voices and Visions for Food Safety website:
QUESTION: Is pet food safe for human consumption?
ANSWER: U.S. laws require that pet foods be processed, so that they are safe for human consumption. Part of the logic behind this is that, when people lose jobs, the sale of pet food increases. Obviously, unemployed individuals on limited incomes are not buying pets. Hence, it is safe for humans to consume pet foods.
Source: Kenneth N. Hall, Ph.D., professor emeritus, Department of Nutritional Sciences, University of Connecticut.