I'm talking about when it comes out
First off, you're probably gonna have a long wait: six months at least, maybe even 10. Certainly not worth arguing about it now.
Second, because it hasn't come out yet, we honestly have no idea how it'll play out. Each iPhone release has seen a slight tweak to the procedure for buying one, but based on past experiences, you can just go the Apple store, and don't need to go through a carrier.
And FWIW: you can walk into an Apple Store anytime and get the Apple "experience." I've bought iPhones at the Apple Store, online, and at the AT&T retail store, and the "experience" ends up being about the same: you hand over a credit card, sometimes you sign a new contract, and in return you get a neat-looking phone in a neat-looking box.
Actually, I kinda didn't like my last experience getting the 4S at an Apple Store so much, because the "Genius" wasn't aware of how iCloud backups worked, and insisted on setting up the phone blank and telling me I had to restore on my Mac at home. I had to meander around the store a little longer while I did a reset and reactivation oft he phone myself, from scratch, and then did the iCloud restore using their WiFi.
iCloud restore was highly impressive. But, it actually would've gone slightly smoother if I had simply ordered online and done it at home.