There's a reason for that... They already produce or import enough food, so with growing plants for biodiesel:
1) you get some small amount of oil out of it.
2) if shit hits the fan, you have local farmers, with all the equipment and knowledge/training, who can immediately switch to food production if needed. The alternative would be to train new farmers, buy new equipment, etc., which would take a long, long time (especially if the government is organizing it), and there's that saying about two missed meals and a revolution, and french leaders really really don't want another revolution.
1) you get some small amount of oil out of it.
2) if shit hits the fan, you have local farmers, with all the equipment and knowledge/training, who can immediately switch to food production if needed. The alternative would be to train new farmers, buy new equipment, etc., which would take a long, long time (especially if the government is organizing it), and there's that saying about two missed meals and a revolution, and french leaders really really don't want another revolution.