These stars were giving to gamers in Europe who bought games. You bought a GC or GBA game, inside was a unique code and you got stars. They could be traded for Nintendo-ringtones, backgrounds, etc. but also - if you had a lot of them - for the collector's edition of Zelda. They're pretty useless these days so I'm glad the star-catalog is being updated.
Edit: Erm... someone already answered that one...
I'm going to buy Zack and Wiki! And you should so too
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