by being the "cha fit ian", the boss can have big influence. being the boss also entitled to a cut of the profit from other members personal venture.
once sworn with blood for life and death, you can "retire" to do legit business or be a community elder, but you can never leave. it's an honor code. you leave, you die. for those who are established, served their time in jail, and have been successful with legit business, why not put more energy and emphasis on the day side than the dark side. and their children are grown, well educated and doing totally different stuff like law or medicine. trusted lieutenants would recruit desperate but promising youths to run the dark side. whipper snappers who are out to prove themselves would thrive in the dark side, and when they grow older, serve time, amass wealth, they would start doing day side business. it's a generational cycle. in sf chinatown, the elders were having a hard time recruiting young guns in the 80s. so they resorted to recruiting fob's. one martial artist fob rose in rank to become de facto dai gor. he was heavily tailed by sfpd and the fbi, and he was busted and served time in jail. now he's out, "turned over a new leaf", but still have his network of thugs running the underground business. he has a brother who is totally the opposite, a bookworm and academic. ironically, dai gor's name is 文 and his brother's name is 舞.