CFDA president Diane Von Furstenberg wants to make Fashion’s Night Out a permanent holiday. Yet did it generate the sales retailers needed? Though it drew a large, exuberant crowd, the evening wasn’t exactly a shopping extravaganza at Barneys. The store’s creative director, Simon Doonan, told us yesterday after Diane Von Furstenberg’s show in the tents that the night was “not incredible from a business point of view, but just from an energy point of view it was fabulous.” He continued, “I think it would be fun to do it again, but we would just have to rethink it a bit because the crowd skewed very young.” Doonan conceded that may have been because the Olsens bartended. What would he do differently a second time around? “Figure out ways to monetize the whole experience. You know, cha-ching!” Doonan said it was impossible to say whether Barneys, already in rocky financial waters, lost money that night. “When you stay open late, you’re automatically accruing operating expenses. So it was not inexpensive,” he explained. Though they had alcohol sponsors, they still laid out cash for more booze — and for that, those Olsen fans are probably very grateful.