For most any phone from AT&T, after the contract is up, they will let you unlock it. This makes since, because after the contract is done, you have effectively paid for it, and it does belong to you. I just recently did this with a Motorola RAZR V3xx. I called them up, said the phone was from an ended contract, and asked to unlock it. There were no questions or uncertainty, just "I can help you with that", and the person then gave me the unlock code and instructions after getting the phone's IMEI number.
This does not happen with the iPhone. After your contract is over, you still are not allowed to unlock it.
In addition, I personally will probably be paying the full ($600) price for my next iPhone, so that I am not tied into a contract. Why shouldn't I be able to have the phone unlocked?
Also, don't forget that you need to enter a contract with AT&T to get an iPhone in the first place. If you decide to get the phone for $200, you'll need to pay an extra $325 - $10 a month if you end the contract early. Plus there's the $36 for activation. If you cancel in the first month, you must return the phone, so you have to pay for at least one month of service, which is $65. So if you go this route, you end up paying a minimum of $200+$315+$36+$65=$616 plus taxes and fees.
So no, it is not in fact possible to have any sort of iPhone for a mere $200. Your complaints about entitlement are misplaced.