Frames aren’t glazed until sold so of course the would be unglazed on display that get stolen……Or do you think opticians are Soo rich they can have about 1000 versions of each frames in stock to account for varying lens types, prescriptions and measurements, high street opticians are actually having a v tough time ATM which is why they take a hard line, it costs about £60-70 to test someones eyes we get paid £20-30 so profit has to be made in glasses, the online guys don’t take that hit so just cream the profit, but don’t worry when the indies go out of business I’m sure they’ll test your eyes obline for you too