The situation is actually much worse. If you go to an optician to get a prescription for eyeglasses, assuming you pay via your insurance, if the optician believes that you will not be ordering glasses from the optician, the optician intentionally and vindictively gives you an erroneous prescription that is off by 0.5 in one eye, leading to a lack of focus when seeing at a distance. It took me many years to catch on to this scam because I had to distinguish it from the prospect of Zenni shipping out bad glasses which they didn't.