This is shelving put at the end of a row of cabinets, creating extra open storage. This is a potential option when you want more storage but you do not have enough room for another cabinet.
The base end shelf not only is a practical way to get more storage but also works as nice decor for your interior. These are customizable features that do not have to match the shelving tiers of your cabinetry, but they have the same aesthetic like the texture or color, so it works cohesively with the rest of the base cabinets.