The "Day 1 DLC" is not "true" DLC. Let me explain:
- Portal 2 is a complete game. It currently does not have any extra levels or story or game modes that you have to purchase.
- None of Portal 2 requires a special code to unlock (ala all of EA's recent titles)
- The "DLC" everyone is talking about is HATS.
The stuff you get from the hats is 100% Cosmetic. You don't run faster. You don't shoot a third portal when equipping it. Your character isn't smaller or larger. It still has to worry about turrets. These "DLC" items are cosmetic changes to your avatar on Co-Op. So, on Co-Op, unless you take your time out of playing the game to notice they are wearing a stupid small cowboy hat, no one will notice.
I see so many times "It's the principle of the thing." What principle? They gave you a $60 game. It has some of the best comedy, writing and gameplay I've seen in a really long time. You got SP and Co-Op, and both are very well done. The graphics on all three platforms are great. However, they aren't hurting anyone. If you don't like the hats, don't purchase them! Leave the purchasing to the ignorant which actually care about the hats. If someone flaunts their needless purchase, simply de-friend them and choose a new partner.
Seriously, all of these "cosmetic" things are not affecting anything. Unfortunately, it has made Team Fortress 2 a fail game, but that is because some of their "farming" and "crafting" changes have required you to be in-game in order to trade/craft. That's a dumb move on Valve's part, but I believe they realized this issue and are not going to repeat the same mistake.
Everyone who is trolling these aggregate rating sites (namely, Metacritic), are simply trolls. 95% of these negative reviews are saying it's bad because they have this DLC. Meanwhile, Valve has a 95 Metacritic anyways, people are getting exposure to their "DLC" boosting sales.
If you seriously want a game to fail, the key is to not talk about it.