Exactly, this is little more than an inconvenience if you're somebody who wants the shader.
That being said, can we assume the redeemable code is on the pre-order receipt? If so, it's whatever. If it comes with the game, then I think people have a right to be pissed. For the record, I don't like this kind of shit, but as long as there are loopholes, I don't mind exploiting them for more free stuff.