One huge gap I see between Euro and American tourists is that the Euro seems genuinely interested in seeing ordinary life in small town America whereas the American bürger really only ever stays within a capitol or around the main sites.
Not many Americans itching to pass through Besançon, Łódź, Kiel, or Ipswich, but Euros are completely gobsmacked by Fairhope, Chattanooga, Middlefield, Bowling Green, and Ocean City.