Fads come and go quickly, and they often take hot stocks with them. But here’s how Krispy Kreme, Crocs, Pier 1 and others survived the rush -- and why they may thrive again. Surviving success We’d all like to think that the market is more rational than kids panting for the latest shoes (with wheels!), or adults willing to line up around the block for a really special doughnut. But in fact, Mr. Market seems ever eager to hitch a ride on the latest consumer bandwagon -- which could be a quirky rubber shoe, a crafty new soda, a luscious treat or a Next Big Idea someone’s thinking up just now. The reason is simple: Trendy stocks can mint millions for those who get in at the right time -- if they also know when to get out. That’s because the public, particularly the teens and young adults who drive so many consumer trends, are fickle. And when fads end, companies without a solid foundation often go the way of the Pet Rock -- or so many late-1990s dot-coms. But those companies with a core br...