When you say "bad glasses", distinguishing the two is exactly something to worry about. I found that the problem disappeared when I started paying hard cash for

When you say "bad glasses", distinguishing the two is exactly something to worry about. I found that the problem disappeared when I started paying hard cash for a prescription, although it still varies by the practitioner. Fwiw, it would be very hard for the government to correctly investigate and accurately prove in court, since it will require a statistical proof over many patients that get tested at both good and bad places.