If you think $200 buys you an iPhone, you're sadly deluded. "$200 with 2 year contract" means you haven't bought anything, you're still paying the mortgage with every phone bill. If you want to buy something and "do whatever you want with it", Apple, Google, and a host of others will sell you an unlocked phone. And it will cost a bit more than $200 (though the Nexus 5at $349 isn't too far off).
On the other hand, if you're fed up with your carrier and would like to switch, you're free to do so. I just did it with AT&T. Walked into a T-Mobile store, asked them to transfer our numbers. The next day I called AT&T and asked, "how much do I owe for the ETF?" I paid the $225/phone (that's how fed up with AT&T I was) over the phone with AT&T. Wait a few days for their accounting system to catch up, go to the web page and enter the IMEI for both phones, and two days later the phones are unlocked. Slapped the T-Mobile SIMs into the iPhones and we were on the air.
I just don't get the sentiment of "unlock my free-with-contract phone two months into my contract, you bastards!" It's not your phone. Now, if Verizon, Sprint, or $YOUR_CARRIER don't as readily unlock your phone as AT&T after you pay the ETF or your contract is up, I'll stand with you in your complaint. Otherwise, I don't see the issue.