It's probably not the most motivating thing to work a minimum wage job. Employees make their dissatisfaction known in silly ways. They probably won't ever receive an award for employee of the month, but at least they can make us laugh a bit.
Bananas can definitely be described as "long yellow things." But why would they put that on the price tag? Maybe the employees were playing a game that day, or maybe they were in a country that never had bananas before. Maybe someplace like Greenland?
If you ever see someone doing what's in the following image, just go the opposite direction.