(a) An offense under Section 13.030, 13.032, 13.037, or 13.039 is a Class C misdemeanor.
(b) It is a defense to prosecution or to the imposition of a civil or administrative penalty for a violation of Sections 13.030-13.038 that a discrepancy between the actual weight or volume at the time of sale to a consumer and the weight marked on the container or a discrepancy between the fill of a container and the capacity of the container is due to unavoidable leakage, shrinkage, evaporation, waste, or causes beyond the control of the seller acting in good faith.