Naw, if he was the supervisor, he would have called out a couple more guys, so he could stand there and watch. His supervisor is probably at another job site or driving around looking important, so he left the vest off..
You're right... guy on the left has been with the company 20+ years, his boss is out "on the road" so he says "F" it, I aint wearing that shizzle, the newbie's in the costume because he's only been with the company for 6 months and hasn't learned the "ins-n'-outs yet... still tryingto keep his nose clean trying to impress the boss in the event he's spying on them all the while the other guys knows the boss man is at "the pussy cat club" having cocktails with the mayor.