I just took my car in for a check-up - and was told by the dealership that the tires has developed "flat spots". They said this can happen when the car is parked for a long time. But I've never parked the car for more than 10 hours - I drive the car every day, about 250 miles/week. Weather has been mild, between 30 and 65 degrees. The dealership is suggesting buying new tires. The tires that are on are "kumho" and were put on -new- by another dealership in August. Any idea how the tires could have gotten "flat spots" - or is this dealer just trying to sell me new tires?