Funny you mention not giving a golly, about 3 years after THAT, I was in town getting the grandparents home ready for sale, stopped in for chips, and a manager very angrily told me I needed to cover a shift (The same reason I quit).
I looked her in the eye and asked "When was the last time I was on the schedule?" el-stare-o-blank-o. It's like a nightmarish hellscape, working in a supermarket.
I still don't get why we went through such extensive training when our actual bosses gave so few naffs.