DLC can expand a game in many ways. Not only can it expand the experience offered by a title, but it can also expand your wallet, take out your money, and place it in the hands of publishers and developers. And, by 2010, EEDAR predicts that "the average AAA title should be able to earn an additional 10% in revenue by releasing additional content through digital distribution."
It's not a hard pill to swallow; DLC packs such as The Lost and Damned and Call of Duty: World at War's Map Pack 1 have been selling like virtual hotcakes, and Sony has been milking LittleBigPlanet in all the appropriate ways. Also, let's not forget about Criterion Games, the company that has been adding value consistently to its Burnout Paradise game. Of course, gamers have been complaining about paid DLC just as consistently.