> The first-sale doctrine is a legal concept that plays an important role in United States patent, copyright and trademark law by limiting the rights of an intellectual property owner to control resale of products embodying its intellectual property.
That means I should be able to sell my glasses to someone without the original creator causing problems with it. It's more complicated than that, but that's the gist.
If I bought these glasses and they shut down the service and refund me, fine, whatever. But what if I bought the glasses, decided 4 months later I didn't like them, sold them on Craigslist for $600, and moved on with my life? After the shut down I get $800 back, and the poor sap who bought them from me gets a pair of worthless glasses and a dead craigslist email. Luckily this company will most likely get away with it because of the "it's more complicated than that" part.