Wanted to add: when a gun is pointed at you (the first time) and money is demanded, your first reaction might be (as mine was) "this isn't happening, is it?" I recall making a slight grin (the guy had a nylon on his head and his face was grossly distorted) and not realizing the seriousness until he grabbed my arm, led me to the registers and threw me on the ground.
Fortunately, these guys were only interested in cash, cigarettes, and wine. Unlike the punk in this article. He was out to kill, not rob someone that night. (pistol whipping a big clue) Fry his *ss.