Smart cards are super cool! The number of real applications is pretty limited, though, with computer authentication being almost all of them (payment cards, yes, but the fallback to 'conventional' processing negates a lot of the advantage). I think that challenge-response NFC authentication will make this kind of technique more practical for physical access control applications.
My view is that the scenarios described in the paper basically amount to "computer authentication", and smartcards would be completely warranted (and not at all unreasonable to implement) here.
