that was one of the best parts.. I havent looked into this very much since I just recieved a notification about that article, but here's what it had to say.
The concept of a self-pour bar is simple: After being ID’d, you open a tab. Then, depending on the bar, you’ll likely receive either an electronically linked bracelet that has your credit card information pre-loaded on it, or a radio frequency identification card that’s roughly the size of a credit card and can easily be stashed in a pocket.