Firstly its FREE so its not greed and its pretty simple, its to encourage pre-orders and more importantly, to discourage piracy, can't believe no ones mentioned it.
It's discouraging piracy by screwing over people who can't pre-order the game.
I won't be able to pre-order before the promotion ends, therefore when I can afford to buy the game, legitimately and fairly, I have to pay even more and for what reason? To make sure I don't pirate the game? I'm sorry so the solution to piracy is to force your customer to pay more money? Isn't that a reason piracy exists to begin with? What this is is project $10 on a new level.
p.s Project $10 -
http://www.escapistmagazine.com/videos/view/extra-credits/2068-Project-Ten-Dollar
The difference being this isn't even coming with the retail copy of the game for people who buy new, something EA have been doing and honestly I don't mind, this is purely for a pre-orders and only pre-orders, and only before a certain date at that.
If you want to encourage pre-orders you can do it with small in game bonus's, DA:O we got some nifty helpful items, nothing game changing. This is not that, this is
CONTENT, complete and finished, that they are withholding from people and then charging them extra for purely because they couldn't, or didn't want to, pre order. If you want to discourage piracy then the standard project $10 works fine, bit of content that requires a key to activate, ok it's a rather roundabout way of doing things but fair enough.
I don't mind DLC, it can really help developers and games, this however is just trying to squeeze more money out of people who are already happy to buy their game new.