When I was in high school
(and still do), but the possibility of both observing people
in states of consumer frenzy
and then taking advantage
of that with a little mall mischief
kept me and a friend of mine always coming back.
The mall in question is of the sort that has glass ceilings that are supported by an ornate system of girders. The two of us would sit in the food court, or on a bench under these glass ceilings and look up towards a corner in the girders, pointing up to said spot and talking back and forth. If we were lucky, eventually someone or a group of someones would stop, look, and then ask us what we were looking at. We would tell them there was a bird (usually something exotic and brightly colored, like a cardinal in winter or a parrot from the pet store) up in the corner, and we would point at it. Of course, there is no bird, but we would have this poor sap looking at this corner for several minutes pointing and saying things like "there, it just moved. Do you see it?" After a time some people would give up, but some would actually claim to see the bird and even, after proclaiming they saw it, admire it for a minute more— playing off any information we gave them about its movements and plumage. They would then pick up their bags and leave as we resumed our position and waited for the next curious person or party to wonder what we were looking at. At the time this was glorious fun.