Not strictly true.
You also have to consider the packaging for stuff that isn't loose. It helps if items are a uniform shape, as the packaging process is mostly automated. And then packs of things have to fall within a range for a particular weight. Because then, it's so many packs to a tray, so many trays to a pallet, so many pallets to a truckload etc. From a commercial perspective it makes sense. And having items a uniform size means that packaging can be optimised to protect the product from as much damage in transit as possible.
The engineer in me totally gets this, especially after having done modules on packaging and robotics as an undergraduate.
However, the cook and forager in me despairs, because we're dealing with products that are subject to the whims of mother nature, and it's the flavour and quality that ought to take precedence, as opposed to the shape and size. Ergo I've no problem buying wonky fruit and veg.
Although sometimes with the wonky / value fresh produce, you do need to double check, because sometimes it's actually more expensive than the non-wonky stuff. Soft fruit is where you have to be *particularly* careful, but that's another matter.
I've just made a lovely apple sauce from apples I foraged from a hedgerow (they're some kind of russett) and some Cottenham Seedlings from the community orchard - none of which would ever make it to the supermarket shelves. But it tastes fabby (added fresh ginger, plus some cinnamon and corriander and sugar), and it'll go nicely with my yellow sticker sausages this evening.