Best before, but not bad after

I'm used to see art on the square, but a milk carton? It made me wonder. 
It is a campaign to throw less milk. Smell the milk before you throw it away, it's often tasty and drinkable after the expire date. 

In Norway we throw away 355,000 tonns of food each year at a value of at least 20 billions NOK. People press the button on the carton if they agree that we shall throw less food, and at least smell the milk before throwing it away.  I was one of the 86029 that agree and pressed the button.  

Cool way to get attention!