I understand that iPhone piracy is theoretically possible, but how can they possibly suggest that 75% of all apps in circulation are on the devices of users who are savvy enough to figure out how to do it?! That's simply absurd. You can't simply download an iPhone app like you would download a copy of Windows or Photoshop. The authors of this report obviously don't know that.
I don't know about the States but people preforming jailbreak services are really common here. You don't have to be tech savvy, just go on craigslist and find someone to do it. $10-20. And voila, free apps....