[UncleOxidant]

Primarily because there are stricter requirements via FDA on the US food supply. If a US producer gets caught adulterating they're going to face legal issues that a foreign producer will not face. Not saying it's not possible that CA producers could be adulterating, but if they get caught there will be consequences that an importer won't face - the importer can just say they were trusting their suppliers overseas.

Also found this (from 2010): "The research team found that 69 percent of the imported oils sampled, compared with just 10 percent of the California-produced oils sampled, failed to meet internationally accepted standards for extra virgin olive oil." https://www.ucdavis.edu/news/most-imported-olive-oils-don%E2...