[...] cash sales at non-gambling outlets within casinos represent 28.5 percent of revenue, up from 22.3 percent two years ago, and bars have increased their payrolls by nearly 39 percent in the past two years, according to a recent study conducted by the consulting firm Tourism Economics and commissioned by the Atlantic City Alliance, which promotes the resort to other parts of the country. For nearly 30 years, Atlantic City's casinos drove busloads of people to their doors, let them play the slot machines or table games for a few hours, and sent them home. If revenue from third-party businesses that lease space at attractions like The Quarter, the Tropicana's Latin-themed dining and shopping complex, are included, Rodio said, his casino's gambling and non-gambling revenues would probably be close to even. Even with the extras, the city's casino revenue continues to plunge, from its high of $5.2 billion in 2006 to $2.74 billion last year, as competition from casinos in neighboring states continued unabated. A poll released in June by Fairleigh Dickinson University found that non-gambling attractions are the most important factor for most New Jerseyans in choosing a casino to visit; 40 percent listed it as their main priority. [...] in June, the Borgata casino opened a $3.5 million outdoor concert center that can hold 5,000 fans with a show by The Hooters, Southside Johnny and The Asbury Jukes, and G.