Nature/Science/Cell are popular because everyone recognizes their "brand" and associates them with interesting, high-impact science. Thus, it's easy for anyone "Hey, we should fund/hire her because she's got a bunch of Nature papers!" It's not miles from the old "Nobody got fired for buying IBM" bit.
In contrast, it's unlikely that one person--let alone more-on the committee has carefully read your J. Soc. Whatever paper and says "This is well done! Get him instead!"