When did underwear become outerwear?

When did pajamas become something you wore to the mall? Or to school? The decline in decorum seems to mirror the decline of our society in general. Have to admit I was an early adopter of de-formalizing dress codes. The only time in my teaching career I ever wore a tie was the couple of years a yahoo down the hall was coming in sporting ripped track pants and rubber boots. That was taking "de-formalizing the dress code" to places it didn't need to go, in my opinion. The Farm Manager maintains her Ed Assistant job at the local highschool. Whereas there once was a "dress code," the dress code today is, so long as genitals and nipples are covered up, anything goes. I see it on the streets around the school. A sports bra up top and short shorts below, with some jewelry and perhaps a little ink in between, tells the world this teen gal is... what? Gullible? Suggestible? Vulnerable?