If you are selling stuff, such as fruits, vegetables and fish, to the supermarket instead of just through your inventory, I remember reading somewhere that you get 10% more for it than just selling it in the inventory (haven't confirmed it myself, but if anyone wants to, be my guest). Thus, I think this is actually a valid question. There would obviously be a reason why the developers included the possibility of travelling to France and sell it, so it would be illogical to dismiss that possibility before someone has actually tested it.