> How would one set out to prove they were not vaccinated?
I suppose a blank vaccine card could be presented, but that assumes that an extra one can't be obtained.
OTOH, why would someone unvaccinated even have a vaccine card in the first place?
Hmm.
Perhaps opening your wallet or purse to demonstrate that you don't have a vaccine card could work, though one could just remove it prior to entering the restaurant, if one is forewarned. Which the sign does. Darn.
Nope, no getting around it. Restaurant patrons are simply going to have to publicly swear (as in raise-your-right-hand-and-repeat-after-me) that they haven't been vaccinated. It's the only way to be sure.