It prevents abuse of power, it's auditable and accountable. Which is something other platforms can't be. Also, it allows to distribute the money not from a central point but from the other users directly. For the moment, there is no STEEM Dollars to Bank...but it will come. Someone could use a service like shapeshift that allows people to buy things in bitcoin directly from steem dollars is a possibility.

In any case, it's an easy door into the world of crypto...which might accelerate the adoption of bitcoin to new niches.