I posted this very experience on another thread.
I read that someone did this earlier, so I gave it a shot. Reserved two phones at the Beverly Center and when I went to pick up, they said I could NOT purchase full price.
Reason being that the phones reserved via website, are technically "online inventory" and not the store's inventory, hence they can't sell me the phone because it's not theirs. Yes, this makes no sense to me at all as the phone is physically there. What they said was the phones go back to online inventory and cannot be purchased by walk-ins.
This rep called his manager per my request, and they both stuck to their guns. Even though I mentioned someone did this successfully at another store, they claimed this was impossible and that person messed up by allowing that purchase.
While in that store I called Pasadena, who also said you cannot purchase full price. The person went as far as to tell me that even if you purchased full price, you HAVE to activate the phone in store. That's a bunch of bull because buying in full makes the phone yours outright and you cannot be forced to open and activate in store.
Now, I've read PLENTY users who had no problem even buying full price on release date, and again someone earlier who reserved online and bought full once he picked it up. I seriously think each case varies and depends on who you're dealing with.
Or I could just be SOL