Most gamers are now used to buying games that have access codes in them. One-time use codes that unlock DLC, multiplayer modes, or other add-ons. This feature is an incentive for gamers to buy "new retail" copies of the games rather than buying used media from the secondary market.
Bethesda and Id Software's RAGE is using a once-time use access code for the single-player campaign. Yes, that means that you NEED the code to walk, interact, travel, and do other verbs in certain areas of the map. That means the specific missions, tasks, items, NPCs and etc will be out of gamer's reach if they buy the game used.
"If you bought the game new, [those hatches] would be open for you," says id's creative director, Tim Willits in an interview with Eurogamer. "You still have to download it, but you don't have to pay for it. Those hatches are all over. Most people never find them. But as soon as you do, you're like, oh. And then you start to look for it. That's our first-time buyer incentive."
But as you can tell, most people never even see it. I can tell you, some people will buy Rage, download that, and still never set foot in those things. They just won't. I think that's fair. It's cool. It's outside the main path. We're not detracting from anything. But I know some consumers, when you can't avoid it, then you get a little touchy subject."