Bench seating gets specified for the way it looks. It gets re-specified, on the next show, for the way it performs. Once a production team has watched a crew set 300 seats in forty minutes instead of two hours — and watched the room hold an extra four rows without touching the egress plan — the aesthetic argument stops being the main argument.
This is the practical case for benches in theater-style setups: the density math, the comfort ceiling nobody warns you about, and the specific conditions where benches are the wrong call. If you are laying out a keynote, a runway, a ceremony, or a product reveal in a room that is smaller than your headcount wants it to be, this is the tradeoff you are actually making.