California Code, Public Resources Code - PRC § 42283

(b)(1) A store may make available for purchase at the point of sale a recycled paper bag but shall not sell a recycled paper bag for less than ten cents ($0.10) in order to ensure that the cost of providing a recycled paper bag is not subsidized by a consumer who does not require that bag.

(2) Notwithstanding any other law, a store that makes recycled paper bags available for purchase at the point of sale shall provide a recycled paper bag at no cost at the point of sale to a customer using a payment card or voucher issued by the California Special Supplemental Nutrition Program for Women, Infants, and Children pursuant to Article 2 (commencing with Section 123275) of Chapter 1 of Part 2 of Division 106 of the Health and Safety Code or an electronic benefit transfer card issued pursuant to Section 10072 of the Welfare and Institutions Code.