Daily Finance – The casino industry commands $37 billion in annual revenue. As far as competitive pastimes go, Americans spend more money on gambling than we do on professional sports. And if it’s the rush that’s the draw, there’s no competition: We shell out $9 billion more on gambling than we spend on coffee and video games combined each year. But when you dig into the demographics of gambling, a troubling trend emerges. Among senior citizens, gambling is a primary social outlet — more so than outings to museums, libraries, and zoos, according to one survey of activity directors from…