‘Buy 6-Get 7th Free’ Includes Coffee, Big Gulp®, Slurpee®, Chillers® Drinks DALLAS, 2015-3-9 — /EPR Retail News/ — 7‑Eleven, Inc. wants its customers to drink up … because the more often they do, the more FREE coffee, Big Gulp®, Slurpee® and Chillers® drinks they’ll earn. Just launched on the 7‑Eleven® mobile app is 7Rewards, an expanded customer loyalty…