The U.S. commercial casino sector (which doesn't include Indian reserves) posted $35.64 billion in revenues last year, with the Las Vegas strip leading with annual sales of $6.07 billion and Atlantic City following with $3.32 billion.

Of the 22 states where commercial casinos operated in 2011, casinos in total contributed $7.93 billion in tax revenue to state and local governments, a 4.5% year-over-year increase, according to the American Gaming Association. 

Gaming in Philadelphia, which has the nation's highest tax rate on gambling profits at 48%, contributed $1.45 billion in casino tax revenues last year, while Nevada, where gambling is the state's largest source of tax revenue, followed with $866 million.

"Any form of intangible entertainment like this can have a fairly big financial impact," said Dr. I. Nelson Rose, a professor at the Whittier Law School and gambling expert who authors a blog called Gambling and the Law.