By this logic no customer would ever get COVID-19 from a stranger at a restaurant. When are you spending more than 10 to 15 minutes away from your table? Let alone in close contact with another person not in your party?
Maybe they should advise playing musical chairs every 14 minutes to prevent spread between people in the party?
That's what they're doing in Iowa:
Officials question Waukee High's suggestion for breaks every 12-14 minutes
I have always assumed that the length of exposure just changed the probability of infection. (i.e 15 minutes = 30% chance, 5 minutes = 10% chance, etc.) If an infectious person spends 5 minutes each with 30 people they're going to infect a few of them...