Who benefits from fair trade? The coffee shop I frequent sells fair trade coffee, so I can feel good about supporting it, even though the only reason I really go there is because I can walk to it.
Honestly, I'm ambivalent about these types of issues. All my "real world" experience has taught me that everything is a tradeoff. If something sounds good (like fair trade coffee pays workers more) there is problemably a down side that most people don't realize. I'm not saying everything is a zero sum game, because that's not true. But I do believe every decision has negative factors that people are unaware of, or just flat out ignore.
They (Hayek, et al) taught me that free trade is a positive sum game. As far as I can tell, which isn’t very far since fair-traders are very ambiguous about their policies, is that fair-trade is neo-Fabianism with new bells and whistles to disguise its past failures. I think it would do everyone good to go pick up a copy of De Soto’s The Myster of Capital from their local library, and find out how to really help the poor, i.e. help them establish a pro-market legal structure.