Yeah, that's the biggest advantage for me. Once I'm done eating I generally want to at least go outside to smoke/vape, if not leave right away, but far too often it takes a solid 20 minutes to wait for the bill to arrive, wait for the waiter to return the bill, and then wait for them to return with my card. When I've used one of these systems, we finished eating, I swiped my card, and then we left.

Plus, the one I used had the ability to arbitrarily split the check without having to have the waiter remember the random dollar amounts to put on 4 different cards.