I have a friend who sells eye wear to opticians. The markup is outrageously high – a pair of Hugo Boss frames that I have which retail for £200 costs his company (the importer) about £6.
Retail sales for Oakley via their website will be an absolute cash-cow compared to their retail sales through authorised retailers.
If if you doubt the retailers are making significant margins on these products, look at the amount of shop/display space Oakley insist on, and the exclusivity arrangements they put in place.
Whilst I don’t know what margins they work to, retailers wouldn’t stock them if the profits weren’t there.