I just stumbled upon an article and the corresponding study that the illegal "pirating" of anime actually increases DVD sales:
http://torrentfreak.com/internet-piracy-boosts-anime-sales-study-concludes-110203/
The study (.pdf download):
http://www.rieti.go.jp/en/publications/summary/11010021.html
Do you think that this also holds for the sale of manga volumes? With the crack-down on onemanga and mangahelpers a couple of months it seems that the bigger publishers were on a warpath with scanlators. Might this change their stance?