Indeed, many in that position avoid doing anything controversial, in the hope that they may comfortably retire eventually without anyone noticing their unfitness for their office.
Chronic unfitness and obesity can also sabotage the reproductive capacity of men, and long-term harm from cigarettes can be passed from smoking father to non-smoking son.
When there is a question of an employee's incapacity, one of the basic safety assumptions in these industries is that employees will self-declare their unfitness for duty.