Shmuel: My problem with your tie answer is that it isn’t limited to bochurim. I know Lubavitch baalhabusim who don’t wear ties even to their jobs where most other employees probably do. They say the reason is religious. When I asked one of the tie-wearing Lubavitchers why he wore a tie and others refused to, he said, “we’re old school Lubavitch.”
Is there some cut-off point at which tie-wearers were grandfathered in?