Israeli 3D Prints in Sand

I thought that this was a pretty cool exhibit that several artists created at the Israeli Pavilion at the Venice Architecture Biennale. They use specialized machines to print in sand . The prints are of Israeli land, and continue to be erased and reprinted as time goes by. Although this isn't the true definition of 3D printing, the resulting prints are in 3D to some respect. The full story on these printers can be found here: http://3dprint.com/5865/3d-printing-sand-israel/

Here is a look at one of the prints, moments before it is erased and drawn out in another way:
http://3dprint.com/wp-content/uploads/2014/06/sand1.jpg

Here is a look at the printers being used:
http://3dprint.com/wp-content/upload...d-printer2.jpg

I don't see where this is 3D printing. It's a giant computer controlled etch-a-sketch.