The Backstreet Boys grossed over $55 million during their recent Las Vegas residency|Backstreet Boys|Facebook

The boy bands of the 1990s and 2000s have evolved into man bands, driving thousands of older fans to their nostalgia-fueled concerts this summer.

According to Billboard Boxscore, the Backstreet Boys grossed over $55 million during their recent Las Vegas residency. The band members are now aged 46 to 54.

Meanwhile, the Jonas Brothers (in their 30s) are playing festivals and bands with men in their 50s, like Boyz II Men. New Edition is doing arena tours till October.

Fans spend big money
Several fans, now in their 30s and 40s, are spending up to $750 on concert tickets, plus $1,500 on travel.

The popularity resurgence is remarkable, considering these acts were once thought to have a brief lifespan of seven to eight years.

Overall, grown-up fans with disposable income are now spending thousands to relive their youth.