nothing. it was his dad's bar and when his dad passed (he died kind of early, in his 50s) it was passed on to him. around the time his dad passed, his brothers were already in their careers/in training for their careers and Rhett was just kind of aimlessly wandering, recovering from a breakup, already working at the bar part time. he had nothing else going for him.
i think running The Zebulon ended up being a good fit for him but who knows what he would have done w his life had that not kind of been forced upon him.