Are you on vacation? Are you staying at the Palazzo or Venetian? Did you bring stupid shoes, and now your feet hurt? Do you need a break from the 100+ temperatures outside? Did you skip coffee this morning, because there is no coffeepot in your (very expensive) hotel room? Do you like to people watch--especially people wearing aforementioned stupid shoes?
If you answered "yes" to any of these questions, then Fashion Show Mall is your place! It's just a sky bridge away from the Venetian, and it can solve any of the above-mentioned problems and/or situations.