The problem isnt the odd person selling their tickets because they cant make it to a game, the problem as John has alluded to is professional touts buying tickets on mass preventing the sale to real fans who are then forced to pay exorbitant rates to the touts.
More admin but a system for swapping tickets with other fans at face value could be made available.
So if you buy a ticket and cant make it you find someone who wants it, contact the company that you bought it from, the third party also contacts the ticket seller who takes their money an admin fee and then refunds you - basically they provide some escrow for the transaction...
The added benefit is that you can be sure that your getting your money and the buyer knows that they are getting genuine tickets and not being ripped off.
Biting the hand that feeds IT
