Money - on-road supervisor makes more than the highest paid driver. Never have to worry about integrity. Supervisor get to take lunches off trace. Get to wear feeder uniforms. No one berates him/her about their over-allowed the next morning. Can take a day-off even if a higher seniority driver wants it off too. Can sell any marijuana found in packages. Don't have 3% of their salary extorted for Union dues to pay for stewards that don't have to pay dues. Never get OJSed. They get to pick the PC they deliver in and always get one with 3 point seat belt. Never have to lock the bulkhead door. DR anywhere they want to. Anybody think of any other reasons?