View Here : Fwd Tire Rotation
Some AWD cars need frequent rotation due to problems caused by tires being different diameters (Subaru is one of those). Also, many small "sporty" FWD cars need frequent rotation because the rear tires have a lot of camber to them to make them handle better.
Having dramatically different amounts of traction on front vs. back is an issue. MINI dealerships refused to rotate tires for customers with over 5000 miles since the last rotation because moving worn (slick) tires to the rear promoted snap oversteer on FWD cars (the back end spinning around).