Queue at Paris Airport

This is the queue at Paris Charles de Gaulle Airport to leave France. The number of travellers overwhelm the  officers checking the passport due to the holiday season.

The actual time taken to process the passport was quite fast, as they do not only need to put a stamp. There was no need to check the computer system.

I wonder why they did not have more officers to handle the crowd? It must be a bureaucratic lethargy.