Bob and Patti Vasconcellos have gone to a local karaoke bar to sing almost every night for decades. Now in their late 70s and early 80s, they hit the floor with their walkers, and the crowd goes wild.

I am not a great singer. I mean, I’m okay, but I don’t have the natural ease and flow of someone born with innate talent. But when I step on stage for karaoke, it doesn’t matter. Karaoke isn’t about ...