Yes they take up a lot of room, but you were only going to fill that with plastic tubs of all the stuff that now fits in the kitchen itself. Those small stainless kitchens with no room to store anything or less than effective IMHO, as you then need to pack all the cooking gear and food into other containers, then unpack to use them whereas this big boy has heaps of effective storage space.
Drifta also do the pull out drawer that fits in next to the kitchen, with a couple of smaller drawers on the front of it. I imagine you could get it without the smaller drawers, as Luke will custom build anything. The long drawer is effective too, and the only lose of storage space is the ~20mm either side and 50mm on the bottom that comprises the drawer itself.