Ticket fraud would not be economic with this method if you can sell the cloned cards. It should be possible to trace multiplied cards (if there are enough of them using the same code) and either shut out the users from the system or even apprehend them when they try to pass the scanners.

The reference test is whether it is easier or less expensive to clone a card than it is to fake a paper (or magnet strip) ticket.

Corporate and government security is a different issue since these may be high value targets even if only a single card is cloned, but as I understand it, these cards are not being marketed for that purpose (which of course dosn't prevent some idiot from using them).