You may be right there.
I've got this weird but often true thought. Dont you think that today's internet audience has become more and more savvy? I think that whenever they see adsense ads which interest them, instead of clicking them, they probably smile an evil smile and note the URL of the advertiser and open it up in a new window. This way the webmaster gets deprived of his rightful income and the advertiser gets a kinda free visitor! For one, I often do this!
What do you guys think?