Apparently it's an "attack on their business model."
Apple argues that "jailbreakers" are breaking the law. And if the EFF gets its way, the company contends, "it will destroy the 'chain of trust' that Apple has carefully engineered into the product to protect users from serious functional problems that often result from unauthorized modifications to the device's OS. It will potentially open up the iPhone to security holes and malware, as well as possible physical damage."
Looks like Apple's biz model is, "You don't buy from anyone other than us or people we approve of. Ever. Period. Now shut the fuck up & buy a next gen [insert shitty iDevice here]."