I have two points, I think.
1) Doesn’t it boil down to who’s getting the spam and who’s encouraging it? I would image that the average everyday hotmail user, for instance, is clicking all their mail to check it, just in case the email with the subject like “Hey, Did they get at you today?” actually contained pertinent information rather than the more traditional “Deez Nuts”.
2) How does this force actually work? I’m not sure that Company A broadcasting spam out of the Netherlands is going to abide by public pressure to supply their mailing list origin. Furthermore, they are hard to track down, as we discovered with the Nicole, Kristin and Christine email blast of 2003.