In 2014, Walmart decided that it would begin a new policy in which its stores would match prices being charged by large Web retailers such as Amazon. For example, if it was selling a 4K television for $899 and Amazon was selling it for $799, Walmart would match Amazon's price. An economist comments that this new policy was more likely to end up raising the prices Walmart and Amazon charged than lowering them. Briefly explain the economist's reasoning.