The rituals of an annual Super Bowl or Kentucky Derby office pool are a distant memory for many sports fans. In much of the U.S., betting is now as easy as opening an app on your phone. The surge in sports betting has come with a surge in ads, with sportsbooks spending billions on TV commercials and billboards. And now some experts are worried the glut of advertisements could be harmful. NPR’s Joe Hernandez has been doing some reporting on this…

Start with just the why. Why have sports betting apps and ads seemed to take off so much in recent years?