Possibly it's fraud prevention, in case payment for the original ticket was fraudulent and chargeback occurs after the ticket is resold on marketplace?
That does sound like a very reasonable thing to do. Otherwise you have a threat vector of steal card, buy ticket, sell ticket, pocket the cash, card owner disputes, now Ticketmaster has paid a stolen identity who took the money and ran.
Anything that can be used to monetize stolen cards will tend to be used for the purpose even if it's inefficient.
Anything that can be used to monetize stolen cards will tend to be used for the purpose even if it's inefficient.