Do you remember the Listo pen? I had to think to remember the name of these pens, but they were the forerunner to our current permanent marker pens, such as Sharpies.
All of your canned goods on the grocery shelf had the price marked on the top with a Listo pen, or maybe they were just called “marking pencils.”
This price marking method was not just used for groceries. I assume that one of the drawbacks to this method of price marking would have been the fact that the mark could be easily removed. Just rub it energetically and it was gone!
The modern method of price scanning probably...