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Why wouldn't there be? It makes the game more fun, instead if run, shoot, get headshot bloodthirsties... And changes it to something else, like coldblooded pro needs 40 aircraft a shot down, sitrep needs 120(50 for MW3), as long as not too many are get xxxkills with this perk.
I'm glad they're not because Treyarch would make you have to use an unlock token on them. Also you'll notice that many of the perks in this game already have two (one may have 3) uses already so you can think of those as pro perks.