User blog comment:Deathmanstratos/New personalization packs, skin packs, and voice over packs announced for Call of Duty: Ghosts/@comment-3964768-20140417010929/@comment-24001421-20140417015837

exactly, money. they want extra money, so they release stuff after the game releases instead of putting it in the base game.

besides that, they have limited space. they might not have had room for this stuff.

or they didnt think of this stuff while they were making the game, or didnt have time to put the stuff in.