Mark Zuckerberg's experiment in social network retail has finally come to an end: on August 12th, Facebook Gifts will close forever. The company's gift feature grew from its acquisition of the social gifting app Karma, selling teddy bears, socks and chocolates drop shipped directly to your Facebook friends. Eventually Facebook discovered that gift cards took the lion's share of sales and discontinued physical gifts altogether. Now the company says it's refocusing its resources on programs that help businesses increase sales through Facebook, rather than selling product themselves. So, in short, the "Buy" button is here to stay, but you'll have to enable your friends' Starbucks habit elsewhere.