I don't know the people, but I recognized the area.
Thats El Mirage dry lake in California.
I also fly from this area, that why I recognized it.
Many people just bring their RV's and park along the edge of the flats and do what ever hobbies they have......RC, Land Sailers, Dirbikes, Quads, race cars, Gyros, Lazairs, Hang Gliders, Trikes, Sailplanes, etc.
Its a huge flat area with tons of room for everyone....5 miles long and 2 wide.
They were at the far end of the flats in the picture below.
Ray