A recent article in the Pittsburgh Post-Gazette talked about tacky behavior in public.  The lead-in talked about stolen wedding cookies:

Heather Vaill had 1,500 of her mother's most delectable homemade cookies set out at her wedding reception several years ago.

"Thumbprints, pizzelles, ladylocks -- all the good stuff," she recalls.

Even with more than 200 guests, the bride still was surprised the sweet treats went so quickly.

"I was disappointed when [a few hours into the reception] I went to get a cookie -- one stinking cookie -- and the trays held nothing but crumbs," says Ms. Vaill, 36, of Plum.

She later learned a cousin had brought Tupperware containers to the reception and absconded with a sizable amount of her wedding cookies.

"A few months later, this same tacky cousin served the cookies she stole at her mother's wedding reception!"

Oh my!  Read the full story at http://www.post-gazette.com/pg/07121/782297-51.stm.  The expert interviewed founded a website full of more:

Jeanne Hamilton, who catalogs thousands of tacky tales spanning the depth and breadth of human rudeness on her Web site, www.etiquettehell.com, says America's self-centered, me, me, me culture is to blame for the erosion of class.

EtiquetteHell.com is both hilarious and depressing, with years of stories about weddings and everyday events.  Both ways, there's plenty to read.