Thanks to my Mom. Expiration dates are important to my family. It seems that one day after something expires it becomes bad. My kids and Grand kids make sure that the food item hasn’t expired before they eat it. Before they used to put expiration dates on can good labels, my Mom would write the date she bought it on the can. I worked at a cannery and she was horrified when I told her that sometimes the cans were in the warehouse for over two years before they put a label on it.
Since I am retired. I have more time to think about important issues. Should buttons have expiration dates? The modern type of Pinback buttons were introduced in 1896. I have buttons from the 1896 election and they are in very good condition. I also have buttons that are 8 years old and are starting to have brown spots on them. Maybe age isn’t a factor. Maybe it is the ink that was used, or the paper printed on or how they were stored. I guess it’s up to you to decide if a button should have an expiration date.
Final thought. Since buttons were not meant to be eaten. Who cares !