Guys
Many years ago men would wear a suit to a movie theater. Not that long ago, men would wear a suit to go to work. Today, try finding a guy that works at an office that has to report to work everyday in a suit; they work from home in their pajama's.
Mob guys were told to dress appropriately when going to a social club. The world has changed, it's about comfort and convenience. The mob is no different, in fact, they would stick out like sore thumbs if they weren't dressed in jeans or gym attire.
Some of the pics you guys see are of guys who were picked up by law enforcement early in the morning and told to put on whatever was on their bedroom floor. Me, I would demand to comb my hair first.