Costco acts more like a cheerful cult than a hard-driving business. Its executives are proud of the fact that the company promotes almost exclusively from within. Even CEO Craig Jelinek, 62, plainspoken and without affectation, once collected shopping carts at a Costco predecessor, and 98% of the company’s store managers have risen through the ranks. Its top executives have been working together for 30 years, more or less, which makes them family as much as colleagues. It also means there are a lot of gray heads now at those budget meetings. ... And therein lies the concern. At that month’s meetings, there were warm and wistful send-offs for six of those gray heads, all senior vice presidents, now retiring. And even though they would be replaced by younger Costco lifers, the succession raises a question: As the company approaches its 35th anniversary, will the replacements keep Costco as Costco? ... It is the question. Lots of companies brag about their culture. But few are as proud of it or as dependent upon it as Costco is. Morgan Stanley retail analyst Simeon Gutman calls it a “super-culture,” which he describes as, “If we continue to serve and delight our customers, they’ll want to keep coming back.