The promotion is St. Patrick's Day sponsored, with BK's press release stating something about not needing to be lucky or Irish to feel the benefits of free fries. The thing that got my juices flowing was the poster's mention of the fries being served with Heinz St. Paddy's sauce. While it doesn't give any other clues, one can only believe that this means green ketchup. I haven't heard or seen anything about green ketchup in years, ever since Heinz's radical and whacked out different colored ketchup campaign fell limper than your morning paper in a rainstorm.
~Fast Food Geek