Actually don't have a problem with this [concept]
Grew up believing the U.S.A. was #1 in protecting their 'People' ...the customer/buying public.
Other countries had plague and deadly Ebola.
No American had to worry about getting sick going to McDonald's.
You work in the food industry, you're going to prove to me that you have antibodies in your blood, etc..
That said, how difficult would it be to forge that simple card? ...unless it was possible for them to immediately type in your name and address and see what location, date, batch and technician was there?
Too much human error/laziness/apathy, IMO.