Jillian Cohan writes in The American:

You can’t steal a concert. You can’t download the band—or the sweaty fans in the front row, or the merch guy, or the sound tech—to your laptop to take with you. Concerts are not like albums—easy to burn, copy, and give to your friends. If you want to share the concert-going experience, you and your friends all have to buy tickets. For this reason, many in the ailing music industry see concerts as the next great hope to revive their business. Concerts might be a short-term fix. As one national concert promoter says, “The road is where the money is.”

But guess who’s drawing the biggest crowds?

But in the long run, the music business can’t depend on concert tours for a simple, biological reason: the huge tour profits that have been generated in the last few decades have come from performers who are in their 40s, 50s, and 60s. As these artists get older, they’re unlikely to be replaced, because the industry isn’t investing in new talent development. 

When business was good—as it was when CD sales grew through much of the 1990s—music labels saw concert tours primarily as marketing vehicles for albums. Now, they’re seizing on the reverse model. Tours have become a way to market the artist as a brand, with the fan clubs, limited-edition doodads, and other profitable products and services that come with the territory.