I have "a friend" who missed his pocket and dropped the phone. Magic impact to the sidewalk shattered the screen. I, I mean "my friend" took it to the Apple store and told them that the screen cracked, then got worse, and here we are. Not exactly a lie, it did crack and get worse, but within a millisecond. They didn't ask if it was dropped and I didn't volunteer to tell them I, I mean "my friend" had.
The guy behind the counter looked up the serial number, tapped a few keys on the computer, wrote some notes, asked if the phone had been synched today, then swapped the SIM card to a new phone and handed it to me, I mean "my friend" and done.
Before you give up, it's worth a shot at the Apple store. They might be a little less willing to swap this week with the launch, but you never know, and it doesn't hurt to ask. If you really want to get into it with them, you can point out how all their sales guys were selling the screen as "unbreakable" when you bought it. I know they were saying that around my store plenty even after this one was broken.