Kraft Heinz Co. was supposed to be different. The packaged-food giant, created in a 2015 merger orchestrated by private equity firm 3G Capital and investor Warren Buffett, was viewed, on Wall Street at least, as immune to the headwinds pummeling its peers in the industry. Sure, it’s tough to find sales growth, with consumers looking for fresher and edgier products and grocers improving their house brands and increasingly giving shelf space to upstart names such as Halo Top and Chobani. But for Kraft Heinz, it almost didn’t matter.