It is misleading to suggest the fee is for Customs attendance, as it is the airport's fee for handling the arrival or departure of a cross-border flight, i.e. even intra-Schengen flights,. As posted on the other side: "Sur les VOLS VENANT et ALLANT hors de FRANCE , un DOSSIER est désormais constitué ( douanes , police , sûreté etc .. ) , cela nécessite un travail et nous facturons."