The parking Rules are - number of people exceeding 4 person states 10 euro per person. At the parking the rule changes to 10 euro additional to the driver.is 10 euro.

Parking value is only the money, otherwise parking in the airport is always better. So you're looking for a lowest price. If your price increased 20-30% when you are in a rush it is cheating. The others clearly stated for +10 euro and were cheaper at the end. Please consider.