Underground pay parking but Free charge

Today, I parked in an underground pay parking close to Le Louvre & Opera in Paris, because it is a very busy neighborhood and I could not find a spot on the street

  

I know they have three charge stations (simple 220V outlet in a steel box, made by DBT) so I parked in the only vacant one, the two others ones being ICEd ... 

I then had to go get the parking manager/guard because it was locked (with a key); After telling me that it was the first time someone asked him about this, he finally found the keys and opened mine, and then I could finally plug in my LEAF and go

3 EV spots, and 2 ICEd:

This charge box is made by DBT and is often found in underground parkings; I think it is pretty difficult to use, because you have to have the key, then plug in, pass the cable through the opening (bottom of the door), and then close, and turn the knob (otherwise the power is not applied and you can't charge) 

Finally plugged in and charging ...