[rsavage]

Herd immunity is gained when people don't do what they are being asked to do by doing exactly what you describe. People should not be gathering in large groups. They get exposed, then expose others, lots get the virus and their bodies hopefully fight it off and the survivors have gained "herd Immunity" because their systems formed antibodies to fight it off. Unfortunately, their exposure to the virus allows them to bring it home with them and spread it to family members - hopefully none of whom are the most at risk - the aged, cancer patients, immuno supressed, heart problems, etc. etc. If I saw a parking lot full of cars, I would have turned around.