Originally Posted by thibderoc

Regarding OP question I'm lost. my first understanding was that he would rent a car in france and then rent another car in Swizterland to go from Paris to Zurich without the renting fee.
but with the LHR flight?? anyway



Schengen is not UE. So, for customs reasons, when going from France to Switzerland, you have to declare cash or goods (according to the law).
By having a french sector in GVA, people living in France can go directly to Paris without crossing any border so without having to declare anything.

If the french sector wasn't there, someone living in France would technically have to go through a custom declaration when crossing the border by car from France to Switzerland to get to the airport and then again when arriving at his french destination.

To sum up : schengen "opens" the border for the people, not for goods and money.