If your paying Retail (no discounts) your not entering a Contract. The reason for a Contract is that AT&T will make back there money that they discounted, so you would buy the Phone (2 years of service). You can buy any phone from AT&T online right now with no contract, but you pay an average of $200 more (8525 sales for $599 and $399 with 2 year contract).
Also, I have owned 2 phones that required Data Plans. You can cancel Data Plans, but you will pay for Data that you or the phone uses.
Also, I have owned 2 phones that required Data Plans. You can cancel Data Plans, but you will pay for Data that you or the phone uses.