the photo was taken at the shop Chaise Longue, a chain which specialises in humorous and original collections of household items and gifts. The product, called “Baguette knife” can be seen on the Chaise Longue website.
A price label is clearly visible next to the baguette in one of the pictures shared on social media saying “Une graine dans le bocal piment” (“A seed in the jar – chilli”), which is the name of a Chaise Longue product. It is a jar of chilli seeds, which is part of a range of different types of seeds in jars.
https://www.reuters.com/article/world/fact-check-knife-concealed-in-baguette-is-from-french-novelty-shop-not-weapon-c-idUSKBN2781KE/