Gov or call 800.952. Hidden fees and charges.What are Deceptive Sales Practices? This section makes it a crime to engage in false or deceptive advertising to consumers about the nature of a product or service. To determine a UDAP violation, a practice must mislead the consumer, the consumer must observe it, and the damages must be material. (13) Making false or misleading statements of fact concerning reasons for, existence of, or amounts of, price reductions. California has enacted some of the strongest consumer protection laws in the nation. One of them is Business and Professions Code § 17500. When marketing products in California, companies need to comply with the State's General Business Regulations. Under California false advertising laws, companies are prohibited from using deceptive advertising in connection with the sale or dissemination of goods.