A lot of people really like Nutella, but when it goes on sale deeply discounted, people really REALLY like it:

From the BBC:

A discount on Nutella has led to violent scenes in a chain of French supermarkets, as shoppers jostled to grab a bargain on the sweet spread.

Intermarché supermarkets offered a 70% discount on Nutella, bringing the price down from €4.50 (£3.90) to €1.40.

But police were called when people began fighting and pushing one another.

It definitely got ugly in some stores:

Love of the chocolaty treat sure turned some people sour.