Near Thackerville, Oklahoma, a town on the Texas border with fewer than 500 residents, what started as a small roadside bingo hall has spent the past 20 years growing into one of the planet’s largest gambling destinations. The WinStar World Casino, fully owned and operated by the Chickasaw Nation, is now the cornerstone of Oklahoma’s $10 billion gaming industry, one of the state’s biggest employers and economic engines. Oklahoma has some 130 cas…