I used to pay a nickel to get a little carton at elementary school. It certainly wasn’t enough to satiate me who was once a milkaholic. I brought it an extra nickel one day and that stupid lunch lady wouldn’t let me buy one because it wouldn’t be fair to the other kids that just bought one. I’m still angry.
You’re supposed to give the nickel to another kid who doesn’t want their milk. Heck, you probably could have gotten it for a penny if you negotiated.