Actually its not
See if i tell you to take care of my cat (iPhone) for 17 months, your responsible for it but at the end of the day its my Cat, you can buy all the toys for it (iPhone Accessories) its mine unless i fully say its your cat (iPhone) to keep
For those who don't understand the story, even though you have purchase the iPhone for $199/$299 its technically not yours but it is your responsibility until you pay every cent for 2 year contract
No offense, but that is a terrible analogy.
And who cares if Apple manages to get jailbreaking considered illegal. Developers will still create methods of doing so and will use different channels for distribution. It will never go away.