Hey and it's only about 5 years too late to realize on-disc, premium "DLC" is wrong! Way to go Capcom!
If it was ready for the disc it should be a part of the game. Simple as that. It is the most egregious way gamers get screwed over. The only thing on-disc that should be locked from the gamer is "online pass" (or more appropriately named 'new purchase') content, special edition content and preorder content.
And let's not pretend Mortal Kombat's f-up is a valid excuse; it's extremely easy to handle it correctly. Two lobby lists; no-DLC in one lobby and DLC-players get access to both lobbies. Or, the better way, since XBL requires a storage space already, make the online require a free DLC file to play against others and then in order to use those characters purchase the 108k unlock key downloads you normally see with on-disc content.
In a groundbreaking victory for the gaming community, Capcom takes all on-disc DLC off the disc, makes you still pay for it, and download it too.
Good job everyone.
That's better than how it is now. It's at least mental lubricant for when Capcom bends us all over by being a dishonest company with day-one DLC that was ready before the disc went gold.