It was supposed to be a big year for Dave Grohl and the rest of Foo Fighters. The band had charted out an international celebration tour for their 25th anniversary, printing T-shirts, stuffing the trucks with equipment, and even sponsoring a limited-edition Coors Lite tallboy.

But then, as Grohl told Stephen Colbert on a Thursday night Late Show interview, “Everything just stopped.”

Grohl still has all those T-shirts — and all those beer cans. (He was freely indulging from one during his interview with Colbert.) But the 25th-anniversary tour is a bust,...