Elevators are basically moving stairs. So for the lazy, the elderly, the sick or nursing, the pregnant, or for the mortally obese, elevators are an ideal solution since walking up the stairs could often be an inconvenience. Also some people are afraid of elevators (confined spaces and claustrophobia and all that). Besides, I like standing on an escalator especially at the mall and see the people down below get smaller and smaller while I go higher and higher.