Local Colour

Just come across a little trivia book, by Stephen Arnott, called "Eating Your Auntie Is Wrong." It has various "strange customs" from around the world, some of which would be useful to provide local detail during adventures.
The "Egg Game" will soon make it's appearance in Shadizar - an unusual gambling opportunity! Lots of opportunities for characters to offend local custom or tradition......
"Haagon slid into the tavern, nostrils assailed by a mix of sour ale and bodies sweating in the heat of Shadizar's summer. A swift glance swept the busy room and took in the colourful mix of customers glad to slake their thirst out of the early afternoon heat.
"Five in a row! By Ishtar's teats!"
The Nordheimer turned, curious at the sudden outburst from a group crowding a large table off to the side of the bar, to see a mixture of scowls and laughter as money changed hands.
"There's an art to it Shemite - I told you that at the off, now pay up!" smiled a lithe man with a distinctly Zamoran cast to his features.
Grudgingly the Shemite - a merchant by his garb - began to push a pile of coins across the wine-stained board until a hand stayed his move.
"Hold there! Five in a row? I want to see that egg before I pay!" The interjection came from a large, swaying Hyperborean, though slightly glazed with wine his pale eyes sparked dangerously.
"Are you willing to pay? Remember, double to see my egg proved, my friend" smarmed the Zamoran, smoothly confident, "Double, my friend."
Several of the watchers growled in agreement. The merchant seemed torn by doubt until the big northerner slapped down a fistful of silver.
"Let me see, you cur!"
With a flourish the Zamoran brought his hand sharply to the tables's edge, there was a brief crunch as it passed and he swept it on to rake up his winnings.
Puzzled, Haagon moved closer to see one of the inn's mangy dogs licking at something that had dripped to the floor.
"Another jug of the Kothian - and another egg!" the Zamoran called to the bar keeper....