The "bancheta" - it's a little bench
(in fact I believe that's what "bancheta" means).
Like so many pieces of a gondola's parecio, this piece is unique.
Most benches and small tables have four legs, some have more,
there are even three legged ones,
but the bancheta has two legs...and two arms.
Those arms rest atop longitudinal supports in the hull.
This unusual design allows the bancheta to sit as close as possible to the inner wall of a curved boat. With a four legged piece, two of the legs would be inhabiting the same space that the hull does.
The arms of some banchete have hooks or notches to keep them in place,
but invariably, every bancheta can get knocked out of place - and when it does, whatever payload is on top of it will tumble to the floor.
That could be a champagne bucket and glasses, food, or even Grandma.
No matter what's on top of the bancheta, it's a bad thig when one comes loose.
Here's a resourceful solution, spotted in Venice:
A simple length of rope, tied in two loops, can keep the bancheta in place.
Sure, it can slide a little fore and aft (and I believe that's part of the intended design), but it's a clever way to keep Grandma from falling and breaking a hip.
And nobody wants that.