Howie Kaplan had zero experience running a major music venue when he bought the Howlin’ Wolf from Jack Groetsch in 2000. Just over 30, Kaplan had spent his entire adult life in the hospitality industry: waiting tables, bartending and booking shows. He was running Rock ’n’ Bock, a neighborhood bar in Metairie, at the time and had just recently started booking bands there when the opportunity came.

“There was an article i...