While it is possible to use advanced features from newer chips, I know more than one actual system where they just use the serial number, even when rolling out more advanced Mifare based cards. So your "that's no longer the case" is a bit too general/optimistic IMO.
And sure, simply using the serial number might pose a security risk depending on the application, but that rarely stops implementors to implement such schemes. More often than not do people believe in security by obscurity, sigh. For a simply ticket system the serial number should be secure enought as it is a use-once application.
And sure, simply using the serial number might pose a security risk depending on the application, but that rarely stops implementors to implement such schemes. More often than not do people believe in security by obscurity, sigh. For a simply ticket system the serial number should be secure enought as it is a use-once application.