Notice that the beginning of this Greek edition is not in chronological order! They started with the Italian/French volume 2, postponing the first years (1953-1955), when Scarpa only did artwork for Martina's stories, to the following volumes. They probably wanted to shoot out the best in the first volumes, so to push more people to get interested in the series. Maybe the responsible for this Greek Scarpa library shares my view on Guido Martina...
You will recall Glénat resorted to this trick on their otherwise-chronological Carl Barks Library — they started in 1950 and only got back to 1942 once they were done with his late stories.
The Greek edition of the Carl Barks Library (Inducks link) was published in the same manner. That's why I wasn't surprised when they started releasing the Scarpa volumes out of chronological order. If this trick helps sales, it's fine by me, as long as we have more comic books and complete libraries coming our way!