I don't know much about bitcoin, so can someone explain me what's the point of having an exchange if there is no way of ... actually exchanging that money.
Read the description on their github. There is no need for exchanges as a central component. People who want goods or services essentially issue IOU's for bitcoins to the seller. Which is why you only deal with trusted people (either people you know or people who have acquired a reputation). Those IOU's can then change hands (but not on a fractional reserve basis).
