My father has been the project manager for design and engineering for some of the largest airports in the world. A classmate of mine when I was in school for Industrial Design wanted to do a project similar to this for his thesis, and he interviewed my father as part of his project. Unfortunately, my father said that such an apparatus would almost never be incorporated into a major international airport terminal due to space, cost constraints, and the need for maximum profit from any space used. Not a great answer for my classmate, but he did go through with his project and passed his thesis, despite my father's insistence that it would not be financially feasible.