I'd like to see more evidence of this, since this is the first I've heard of it!! If its the case that you've pre-ordered the game, then you should receive the extras for free, like in all cases?
I have to say, if its the case that you pick up certain content on pre-order, but it becomes available on XBOX Live for a price shortly afterwards, then there's not much anyone can do about it - if they want it, they pay for it.
Correction: I've just read the linky you've put in - the OP on the other site stated that he either bought the normal edition for £39.99, or "The Naked City" edition for £41.99, which will have extras, and comes in a snazzy box.
To me, that seems pretty standard. Perhaps there's a misunderstanding with what was constituted as pre-order extras, and limited edition extras?