Festivals have long included games of chance, from dice at Saturnalia to teen...

https://mike-wiki.win/index.php/Is_Lunar_New_Year_Mahjong_Usually_Small_Stakes_or_Serious_Money%3F

Festivals have long included games of chance, from dice at Saturnalia to teen patti during Diwali and mahjong at Lunar New Year. Setting a clear end date using calendars helped keep gambling part of the celebration, not a year-round problem