You're not getting what you paid for; you're getting a complimentary case to address the "horrific loss of signal power" due a design flaw. Consumer Reports said the iPhone 4 is the "the best smartphone on the market" according to its test, but doesn't recommend it (it instead specifically endorsed the iPhone 3GS running iOS4) because of the antenna design flaw.

Sounds like you're well on your way to the right attitude for that store visit ;-)