Nadja AsmusYacht charter broker, DMA Yachting
Yes, and they are the reason the water is so clear. French waters protect their posidonia seagrass meadows, and anchoring on posidonia is prohibited and fined, with dedicated eco-moorings and regulated anchoring zones in the busiest bays.
What this means for you as a guest is almost nothing, and that is the point of a crewed charter: your captain knows the legal sand patches, books eco-moorings where needed, and plans the route so the best stops are secured rather than hoped for.
It does reward booking with a crew that knows the coast, especially in August when the good spots go early. Full detail: anchoring rules and posidonia regulations.