Why this tray earns its place
A cut cake on an open counter has two problems, and a cover solves both. The first is the cut face, which dries out from the moment the first slice leaves — by mid-afternoon an uncovered sponge is noticeably drier at the edge than it was at ten, and that is the slice a customer is looking at when they decide whether to buy. The second is everything in the air of a room where people are eating and walking past: an open counter is expected to have its food covered, and a cover is the simplest way to keep that true all day without moving the cake off display.
At 300 mm it is a round cover, which is the shape that matches a round cake on a tray or a stand and takes a predictable circle of counter rather than a footprint that has to be worked around. Plastic is the practical choice for something lifted and replaced dozens of times a day: it is light enough to come off one-handed while the other hand holds a knife or a plate, it does not shatter when it goes off the edge of a counter, and it wipes down between services. Lift, cut, serve, replace — the cover only earns its keep if putting it back is faster than thinking about it, and a light one is.
