Last fall, Kohl's (NYSE: KSS) launched a pair of interesting partnerships with Amazon.com (NASDAQ: AMZN). In 10 stores in the Chicago and Los Angeles metro areas, it opened Amazon smart-home boutiques. Meanwhile, 82 Kohl's stores (also in the Chicago and Los Angeles areas) began accepting returns for Amazon.While some pundits predicted that these moves would backfire for Kohl's, they have contributed to its improving sales and earnings trajectory instead.