I think you misunderstand me, because I didn't describe the issue properly. But anyway, good idea to post an example, to make the description clearer:
"Edition","Foil","Language","Name","Condition","comment","Count"
"Urza's Saga","","English","Planar Birth","NM","Rare Folder 1","1"
"Classic Sixth Edition","","German","Tariff","NM","Rare Folder 1","2"
"Urza's Saga","","English","Opal Titan","NM","Rare Folder 1","1"
"Urza's Legacy","","English","Mother of Runes","NM","Rare Folder 1","2"
"Urza's Saga","","English","Songstitcher","NM","Rare Folder 1","2"
"Odyssey","","German","Beloved Chaplain","NM","Rare Folder 1","1"
"Urza's Saga","","English","Monk Idealist","NM","Rare Folder 1","1"
"Magic 2014","","English","Banisher Priest","NM","Rare Folder 1","1"
"Urza's Legacy","","English","Peace and Quiet","NM","Rare Folder 1","1"
"Urza's Saga","","English","Clear","NM","Rare Folder 1","2"
"Urza's Saga","","English","Humble","NM","Rare Folder 1","4"
"Shadows over Innistrad","","German","Silverstrike","NM","Rare Folder 1","1"
"Urza's Saga","","English","Defensive Formation","NM","Rare Folder 1","1"
"Magic 2014","","English","Blessing","NM","Rare Folder 1","1"
"Classic Sixth Edition","","English","Castle","NM","Rare Folder 1","1"
"Urza's Saga","","English","Serra's Embrace","NM","Rare Folder 1","1"
"Classic Sixth Edition","","German","Castle","NM","Rare Folder 1","1"
"Fifth Edition","","German","Kismet","NM","Rare Folder 1","1"
As you see, I don't have any "date added" field in my CSV file. Therefore I thought it might be logical, that deckstats collection manager fills that filed automatically during the import process, because it just makes sense to populate the filed with today's date, because today is the day I import them.
Hence my question: Bug or feature?
Hope I made my question and description a lot clearer now!