The French plantation owners were occasionally forcing the African slaves to work without giving them food, and the main reason for that was because they were occasionally rebelling against their owners.
Even if there was just one of the slaves that was going to stand off and disobey its owner, or if he/she tries to escape, all of the other slaves owned by that owner will share the consequences.
In this way, the French were trying to demotivate the slaves to make troubles as it was not only the person that did something going to be in trouble, but also his family, his friends. It was a tactically well played move by the French to keep order, as most of the slaves were not going to dare to do such a thing and because of them all the others to suffer too.