Today in Arcata, I was in my car, parked opposite a business where several maskless employees were arranging outdoor tables. Masked, I left my car, walked over to them, calmly explained they may be setting an example for others, and walked away. They entered their place of business, and emerged wearing masks. I believe they just forgot, or even if they didn't, I'd like to think realizing they were inadvertently setting an example was persuasive. Something to try, if you encounter similar situations.
Jeff Knapp, Arcata