It is OK, going into France by a customs field as required. But once you are in France and want to tour around you start to discover that many places will only allow use of a Total fuel card.
A large number of the French club fields are Total only as they don't have refuel staff or any staff around most of the time. When I was in La Roche last week the guys in the club explained that they get the fuel installations virtually free from Total and it is Total who won't allow the machines to be converted to take credit cards.
Ferrying aircraft that have tiny tanks across France means a lot more careful planning for fuel stops these days!!