Exactly. Their function is creating market-beating returns for their investors. Nothing else.
There was a great interview with Josh Reich from Simple on Mixergy recently [0]. Before Simple, he worked at a hedge fund but didn't find the work to be fulfilling because he didn't feel that he was solving a problem for anyone, or making people's lives better (he had studied to be a doctor prior to that as well). He summed it up by jokingly saying "I've never had someone come up to me on the street, saying 'I need liquidity!!'".
There was a great interview with Josh Reich from Simple on Mixergy recently [0]. Before Simple, he worked at a hedge fund but didn't find the work to be fulfilling because he didn't feel that he was solving a problem for anyone, or making people's lives better (he had studied to be a doctor prior to that as well). He summed it up by jokingly saying "I've never had someone come up to me on the street, saying 'I need liquidity!!'".
[0] http://mixergy.com/interviews/joshua-reich-simple-interview/
edit: wow, there is some hedge-fund sympathizer down-voting every post that doesn't buy into this "social function" premise.