When I think of cheap knock-offs I think of things like a Rolex watch or a Gucci handbag, but apparently knock-off food is a $10-15 billion industry.

I don't even mean the faux organic stuff sold as such because some shell company in China claims it is organic and no one bothers to test it, actual food in real supermarkets is sometimes fake, or at least misleading, according to Shaun Kennedy, associate professor of veterinary population medicine at the University of Minnesota Director of the National Center for Food Protection and Defense.

By that he means food with fillers, ingredient swaps and misleading labels, including in food that we pay a lot more for, like extra virgin olive oil. Christina Medici Scolaro at Big Data Download cites a UC Davis study which found that some extra virgin olive oil is not even olive oil. 69 percent of imported samples failed U.S. Department of Agriculture sensory standards for extra virgin olive oil and negative sensory results were confirmed by chemical data in 86 percent of the cases. Instead, it had substitutes like canola or sunflower oil.

Credit: Evaluation of Extra-Virgin Olive Oil Sold in California

Kennedy was also on The Dr. Oz show a few months ago discussing these counterfeit foods. Yes, just this once, I link to Dr. Oz for a positive reason. Because he's right, people are paying for a product and should not be misled.