Companies swindling customers by overcharging their cheap, synthetically made products?

Why do pro-republican clothing companies like Macy's, Nordstrom, Kmart, and Walmart overcharge their very, very cheap clothing that are made out synthetic materials ? I see clothing like gloves, hats, and shirts that are made of synthetic material like polyester and acrylic. If you don't know, Polyesters and acrylic are made of different types of cheap PLASTIC, which are made mainly in China. I walked into their stores to buy some thick and bulky mittens and hats for winter, but saw only their very overpriced cheap clothing.They were really thin and flimsy. Plastics are not designed to keep you warm during winter at all. Plus, how they make and distribute these plastics are very harmful to the environment.