I have made a listing of the optical on-line companies over the last few years and there are plenty of them, you can find it at http://optochemicals.com/web_listing.htm, then scroll towards the bottom of the page and you will see the whole section. My web listing has close to 1000 optical lnks.
Three of the highest traffic ranking ones belong to Essilor who makes lenses and frames these days, so they will make some money somewhere selling on-line and they are not stupid.. They just purchased the latest USA located one a few month ago.
They also own GKB, the largest lab in India with over 500 employees in locations all over the country and has launched the largest on-line optical a few years back.
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