Well, the Pontus thing hardly counts as a DLC. Since it's free, it's more like "look, we made this for you because we had some extra time even though we didn't really plan to earlier". The Greek thing, on the other hand, is a preorder bonus -- also nothing new. Companies have been offering enticements for gamers to lay their money down in advance for years.
That said, yeah, I don't really see why they couldn't just include both in the base game at this point, but meh.