Capcom is sorry that some of its fans are not happy about the chosen method of delivery for the DLC, we believe that this method will provide more flexible and efficient gameplay throughout the game's lifecycle. There is effectively no distinction between the DLC being ''locked'' behind the disc and available for unlocking at a later date, or being available through a full download at a later date, other than delivery mechanism. - Capcom statement

I would say that there are some very fundamental differences in those two things. On-disc locked content means that data was prepared and pressed for launch. Actual DLC is content that is developed after a game's release, be it partially or fully. If Capcom feels there's no difference, why don't they start labeling their games with a 'On-disc locked content' sticker?