Today’s invention is a double-whammy for those of us who have to do supermarket shopping.
1. The checkout system knows the identity of every item on the conveyor belt. This allows it to order these items for packing so that the most fragile* ones are always at the top of the shopping bags (a domestic error of gargantuan proportions is apparently to put the milk on top of the bread).
This ordering might be achieved by holding several bags open at once. A deliver chute would fire each item at a bag which was not yet full and whose last added item was less fragile than the current one in the chute.
Some bags would of course remain forever part-full -if eggs were added to a bag with a jar of pickles, for example.
2. To limit that problem and to save on the number of plastic bags used, these would appear as a cylinder on a roll. When a bag has something very fragile added, it is sealed with a seam across the top, so that bags may contain different volumes.
(*Every item in the supermarket could be pre-rated in terms of its vulnerability to damage by a panel of hyper-careful shoppers, so that product fragility would end up in inverse proportion to depth within a given bag).