I agree, there's probably not just DLC things but other things that bungie have in place - like VoG as well, it was there at the start but not unlocked at release. This is just a side note, but I also don't know what was included in the expansion packs, I bought the digital copy and downloaded and installed the expansion packs at the same time. While we don't have access to it, some of the content related to these packs is installed - I'm not saying this is what is being shown in these videos, but it's still content on the HDD whether the game picks any of that up yet or not is hard to say.