MrTan
macrumors regular
When you reserve your iPhone, they ask for your Apple ID, so they know your name, email etc. That's what I'm guessing they will be using to tie you to your reservation - your name. You just say "Hi, I'm Steve and I'd like to collect my reserved iPhone" and they say "Sure Steve, right this way"!
I don't think you need the email, it doesn't contain a reservation number or anything, so it's just for piece of mind.
although they do have your card details with your Apple ID.