They also do it this way for the beachfront shows.
I don't know this event, you'd have to write the linked aeroclub for more information. Or maybe more information will follow.
The Sanicole airshow, in Belgium which I do know, is also at a small airfield for leisure flying. For the airshow the teams fly from a nearby airbase, but that doesn't stop them from performing their full displays (had the Red Arrows, Patr. de France, Patr. Suisse, and also the Frecce some years ago, I think).