I find it hard to believe that people are willing to save ~8% on clothing purchases after driving a minimum of 30 miles (Hudson or Prescott WI), 60 both ways (making for minimum 2 gallons of gas = $6+, requiring a MINIMUM of $75 spent on clothes per purchase). Take in to consideration longer drives (SD, ND, IA, etc) or people who fly and stay a night in a hotel. I doubt sales tax is a major reason anyone comes, perhaps a slight bonus when they get there. The real reason is the large concentration of shops, restaurants, and entertainment in a convenient location to the airport and hotels and typically a variety of stores they wouldn't otherwise find in their hometowns.