I just bought an expensive pair of Prada sunglasses for $350. It's my first pair of quality shades. Before this I only wore those fake Ray Ban's and Oakley's sold by the street hawkers. I agonised over my choice at the shop, alternating between two pairs - a pair of Ray Ban's and the Prada pair I eventually chose - for over half an hour. Finally I chose the Prada's as the Ray Ban's were a bit too big for my face, I felt (although people around me assured me it fitted properly).
When I said "I'll take the Prada," the salesperson then took me through the details that normal people wouldn't understand or notice: like the polarised poly-something material the glasses are made of (i.e. tough plastic) and the titanium screws that strengthen the structure and differentiate this pair from the fakes and cheaper brands. Out came a complementary $1.50 plastic case with a little cleaning cloth inside. When I pull out my card to pay, the salesperson stops and says, "This is an expensive investment you are making, it is worth protecting. We have a care kit that is well worth it." Not wanting to be rude, I allow him to pull out this care kit which was housed in a tiny little zipped semi-leather bag.
He shows me things I didn't know existed for sunglasses: a little screw driver kit to tighten my Prada's every so often, because apparently the screws become looser and looser each time you open and close the arms. An anti-fog solution, because these new oversize shades fog up when you wear them as they sit so close to your cheeks and forehead. And then there was a non-abrasive special cloth with micro-fibres for optimal care.
At $12 I declined the care kit. Firstly, what happens when I run out of anti-fog solution, and secondly, what won't a good wipe with any old soft cloth fix? Next thing you know you will be required to send your pair of branded shades for an annual service. If that day comes, watch business boom for the hawkers.