I just bought some tires from Tire Rack. Can I just walk in to Walmart and buy road hazard warranty from them? I won't be installing the tires there (don't trust these guys with tire installation). TR wants 110.00 for 4 tires, while Walmart is 9.76 per tire, which comes to less than 40.00 for 4. So, has anyone bought road hazard from Walmart without buying or installing tires there?