San Francisco prohibits pharmacies such as Walgreen's from selling cigarettes, but not grocery stores or big box stores even if they contain licensed pharmacies. Walgreen's sued contending that this distinction lacked a rational basis. The Superior Court agreed, but the Court of Appeal held that Walgreen's could state a cause of action (here). The court held that the City's rationale for the ordinance--that cigarettes should not be sold in retail establishments such as pharmacies that are identified in the public mind with health--did not apply to chain stores like Walgreen's, that typically sell products that are largely indistinguishable from those sold in grocery stores. The court also held that the city could not defend its disparate treatment of pharmacies and grocery stores by the need to keep supermarkets in San Francisco.
I think this case has a shot at Supreme Court review. The court's opinion is certainly less deferential to the city that courts usually are in evaluating legislation under the rational basis test.