America Goes Casual: Slobs and Big Mouths

Sometime in the early 1980s, when David Patrick Columbia was working as a writer in Hollywood, actor Bill Cosby started an alarming trend that defied the industry's longstanding culture of formality.

Despite torn pants, cell phone rage and lack of manners, there is hope, say etiquette experts.(ABC News Photo Illustration)

Cosby — at the height of his popularity as Cliff Huxtable on "The Cosby Show" — walked on a Hollywood set in a pair of Nike sneakers. Before long, everyone followed suit.

"In the old days of movies, every man went to work in a jacket and tie and he didn't walk into the studio if he didn't have a hat on," said Columbia, editor and co-founder of the New York Social Diary, which chronicles the city's elite.

"Cosby was big star, and within a month the director was wearing them," said Columbia, now 66. "In six months, the assistant director and the script girl were wearing them. Now everyone all over the world is. One man with authority and position changed the costume."