WHY do you put round pizza in a square box?

Everyone's favorite Italian food, pizza, is traditionally made in a round shape, yet couriers deliver it in a square box - what could be the reason for this, and what is the purpose of the small plastic "chair" inserted in the middle of the pizza?
Cost-saving and practical at the same time

When you make a pizza at home or order one at a restaurant, it is usually baked in a round pan and served/served to you on a round plate, however, when you opt for home delivery or courier delivery, you always receive your favorite in a rectangular cardboard box
. The reason for the phenomenon, which at first seems strange, is actually very simple: it is much cheaper, simpler and more practical for manufacturers to produce rectangular boxes, and pizzerias are of course also supporters of the most cost-effective solution, which is why they have no intention of obliging the cardboard industry to produce round boxes.

The rectangular box can be folded from a single piece of cardboard into the desired cube or cube shape, and the boxes can easily be placed next to each other or on top of each other, so their storage and transport is particularly simple and cost-effective. A round pizza box would not have any other real benefit apart from aesthetic aspects, because the lack of corners would not save a lot of space, on the other hand, the round boxes could roll and tip over more easily, not to mention the fact that the round box would have to be assembled from several parts, which would significantly increase the production costs.

There is also a round box

Cardboard boxes were not used for the delivery of pizza for a long time, in the 1800s, for example, the delicious pasta dish was sold for takeaway in special heat-insulating metal boxes, while in the first half of the 20th century in America, street vendors offered pizza by the slice, the slices were placed on a cardboard sheet and then served in a paper box to the buyer.