Campaign creators decide where the money will go if an offer is accepted.
They can choose for the target to be the fee recipient, if the fee should go to a charity of the creators choosing, or to a charity of the target's choosing.
These options can be chosen for different reasons-- not limited to but including:
A creator believes that a target is more likely to accept an offer if it benefits them
A creator believes that a target is more likely to accept the offer it's for a good cause
A creator is starting a campaign specifically to help an organization they believe in
Each campaign is created for different reasons, so this will always vary from campaign to campaign.