I wouldn't rule these out entirely, whilst that are not the only issue they are just as important as what you have highlighted. If spamming/malware didn't yield a profit they wouldn't do it. After all spamming your in box with adverts for penis enlargement, Viagra and various other junk wouldn't happen if the company buying/making the software had nothing to gain. Problem is there are people who click that link and buy it, whilst it may be a vast minority its enough to yeild a reasonable profit and in a commercial world profit is everything. Also if the law was tight enough to track and shut these people down with hefty fines they would stop and find new ways to market their products that do not involve a guaranteed court case which will wipe their company out and bankrupt them. Also, as you highlight, is users X and Y knew how to protect their computers and in boxes like user their spamming / malware would be useless and it would end. I am not entirely sure the software / Internet companies rule the web, whilst they have some control they cant stop everything. Just look at the recent Digg.com issue with the HD-DVD crack code.