The difference is that, when handing a card over to a clerk, you usually get to see the individual & keep an eye on your card (most of the time), and nowadays we're offered the device itself that we can swipe/slot the card in & PIN/sign, so actually handing a card over is becoming less of an issue.
I've done a real-world test with my own NFC-enabled mobile & this card, simulating the card in my wallet in my right jean pocket & someone (wife/brother/dog/whatever) sitting next in a seat to me with the mobile in their left - you can get real close in situations like a rush-hour bus, crammed office elevator, cinema, busy pub or event queue.



