Ok, we get it, online passes are a thing now and they seem unlikely to disappear. Since I buy the games I really want brand new and I'm sure the majority of gamers do as well, it's just pretty evil, rather than the be all and end all of a purchase. That is if the online pass works, which, I think it's fair to say, is a little hit and miss these days.
First huge sections of Arkham City were inaccessible thanks to the included Catwoman code sometimes not even being printed on the card (or just plain not working), Battlefield 3 had similar issues at launch thanks to a mix up with retailers and now Ninja Gaiden 3 is having issues concerning the code as well.
If you've tried to redeem the code and are having issues, Tecmo Koei are going through the motions and hope to fix things sooner rather than later, or so they have explained on their Facebook page.
"We are aware of the issue with the Online Pass for Ninja Gaiden 3 and are working to resolve the issue. For those of you with the PlayStation 3 version of the game, the online pass will be redeemable by 4pm Pacific time. For those of you with the Xbox 360 version, we are currently working with Microsoft to resolve the issue and we will keep you updated.
"Thank you for your patience as we work to resolve this matter."
I think it should go without saying that if you plan to limit sections of your game, you should at least make them open to people with the right to get in. It just goes to show how haphazardly these passes are being included in games and, really, it's an insult to people spending money on your product.