I'll explain. Behind the Magic Neep there are two doors that lead into a small open stock room. That room leads into an air-conditioned stock room (this room also serves the mechanism for the only working chimney in Hogsmeade). Outside that enclosed stock room AND behind the Snowman cart is an open area that services both Neep and Snowman Butterbeer, holds a small vendor cart that is stationed outside of the castle, and has a Butterbeer station for when the vendors go out and fetch Butterbeer. It hosts all that, and two cooler trailers. There is also access to the mechanisms behind the windows of the Southeasternmost part of Hogsmeade, but that's unrelated.
Now, because of the popularity of Butterbeer, the vending station and service area for the cart won't be moving. Something different could come out of Neep's small section, but there would need to be a serious reorganization of space and resources. Apart from fruit, I'm not so sure that any food could (or should) be prepped there, so I think Neep's relatively small assortment works out well, though the cart does create a spacial constraint leading to a smaller bottleneck, and it has also been rammed into several times by service vehicles, so that's as far out as anything will really ever go.