All of our carpool meeting notes have called them the wavy benches. I think the Kiss & Ride title is for the area, not for the benches - the DC metro has them as well (with big signs that say Kiss & Ride, which Alewife doesn't have). It's what happens when someone is being dropped of, as far as I know ("Have a nice day, dear") rather than where someone hangs about waiting to be fetched.