They can't, they need him.
Everyone has some redeeming qualities. In Negan's case, it's his ability to think outside the box, his leadership skills, his managerial style and unique ability to motivate people. Add to that his sense of humor and cheerful disposition as evidenced by his always smiling.......
Who wouldn't want to work for a guy like that?
“Who wouldn’t want to work for a guy like that.”
Maybe someone who didn’t want to get killed with a hard knock on the head....