Obviously Apple had to make a deal with some carrier to get the iPhone out of the factory. They chose AT&T for whatever reason. But, non matter who it was, they would probably have had to go with an exclusive deal. Period. I have no idea how long that original contract runs, nor is it particularly relevant, in my opinion. It
will run out and the rumors are very strong that it may already have. At least some are reporting that Apple is making a version that runs on Verizon's network. The fact is that, unlike Europe (and most of the rest of the World) there is no "standard" network in the USoA. So, to get all the capabilities of some smart phones, they must come in different versions or multiple network chips. I'm not holding my breath waiting for any "standard" to come along before my great grandchildren retire!
Another reason people wanted to 'hack' they iPhone was to get around the limitations Apple has in its hardware and OS. Of course, many of those restrictions are to help maintain stability of the phone. I want my cell phone to work as a cell phone, always. Anything else is secondary. If all I want is a 'brick,' I have of left overs in the back yard.
Of course, there are also those who chafe at the insistence of Apple that apps must come from the App Store. Frankly, I wish their controls were a little tighter!
But that's just me. I have other things to do besides worrying about not being able to get a porn app from Apple...
I see no real problem with 'hacking' any product that you own. Software attempts to claim that you are only 'using' it and don't really own it. That's for the courts to decide. But I absolutely, positively think selling anything as your own that is actually created by someone else is plain, old-fashioned, blatant thievery. That said, I'm not aware of anyone trying to sell a jail-broken iPhone, although there may be some. In any event, the warranty is void and I think any attempt to try to make any manufacturer of a product repair it, under a warranty, is also thievery. It is probably easily argued that jail-breaking is legal, but being legal is not the same as being required to service something that has been abused. To me, it's simple contract law: You do this and I'll do that. If either of us fail to uphold our duties, the contract is, at best, null and void, at worst, damages may be required. Next!
Finally, jail-breaking has been around well before the iPhone, it's nothing new. It's not even limited to electronics. Sometimes, it's even been used by incarcerated people!!!
"Let the breaker beware!"