What kinds of things could you do at a store that would be harmless pranks?

  I’ve actually done this. 

  It was the Christmas season about 15 years ago in a JC Penney at a local mall. I had just left the office, so I was dressed in a dark blue business suit, silk tie, highly-glossed black leather shoes, the whole nine yards. I was in one of the clothing sections, a customer approached me and asked me some question or other about the merchandise, and at first I was a bit confused as to why she would be asking me, but before I said anything to her about it, I realized that because of the way I was dressed, she 
thought I was a store employee, possibly a management-level one. Immediately, I decided to pull a fast one on her.  I answered her question, which satisfied her, but maybe a little too much, because she then asked another. I answered that one too, and another nearby customer heard us and in turn approached me for help. Soon, I was getting out of my league, because I didn’t know the correct answers, but I was having so much fun that I didn’t want to stop. I bluffed my way through the answer, not knowing at all if I was even close to being accurate. I had the chutzpah and ego-driven audacity to approach a third customer, tell him he looked as if he needed help, and ask him if I could be of any assistance. He also hit me with a question too difficult for me to answer, so I tried bluffing him too, but out of the corner of my eye, I saw a real JC Penney employee take notice of me from a few aisles away. She began to make her way toward me and the man I was “helping”, so I knew I was about to be busted. Quickly, I said to the customer, “This isn’t my usual section, I was sent over here to help with the overflow of shoppers, so why don’t I get you somebody who normally works here. Hold on, please.”
I left him there and quickly met the saleslady halfway between where she had noticed me and where I left the customer. As her name tag came into my view, without even slowing my stride, I quickly said to her, “Miss Real Employee, that gentleman has some questions, would you be able to assist him, please?” And without waiting for her response (or giving her a chance to ask who I was), I just kept walking past her at a brisk pace and disappeared from that part of the store, going straight for the exits and to my car in the parking lot.
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