Cupping is not uaually the tire mfg's. fault. It truly is a suspension/alingment problem. Adjustments to tirea (warranty wise) ar going to be on a pro-rated treadwear basis, even at that. Also tires should be rotated and balanced every 5000 miles. Check your tire pressures often, and watch closely for signs of unusual wear. I get alignment checked every 10,000 miles just as a preventive measure. It doesn't cost that much in the long run.
If you aren't driving off road or on snow a lot, I'd suggest getting a set of all weather "touring'" tires. You'll get a much better ride, handling, and much quieter. A good, privately owned tire shop will give you good prices, and take care of your tire mantenance needs quite well, compared to the car dealer or a big chain tire shop.