Anyway, it's a complicated issue that lots of people feel very strongly about, including veteran rock critic Michael Azerrad, who writes at length about it here. He argues, as I have, that if a reunion continues for too long without producing any new music, it can get ugly:
It's one thing if the band is making new music, but if they're just playing an entire album in order or just playing the "hits" without even bothering to reinterpret them because the audience expects faithful versions, then they're just a human jukebox, a tribute band to themselves. At that point it's about being a museum exhibit, fulfilling expectations instead of challenging them. And that's no better than the Who or Eric Clapton or Pink Floyd trotting out the warhorses for paunchy, affluent boomers eager to relive past glories and erase, if only temporarily, their boring, past-it present.
I realize even this is a difficult argument to make in this day and age, because surely a huge percentage of today's biggest indie-rock bands, would say they have no problem with the Clapton/Floyd/Who thing. I don't know if it's a genuine lack of principals, or if it's simply self-preservation—either way, we're going to be dealing with the reunion tour thing for a very long time.
Azerrad makes one other interesting point, not about the artists' willingness get the old band back together, but about the public's increasing demand for them to do so:
The iTunes Age has brought even the most casual music fan a few mouse clicks away from heaps of obscure but legendary music that they missed the first time around. Now, those bands have vastly bigger audiences — like, orders of magnitude bigger — years and sometimes even decades after they broke up. Consumers from this large on-demand culture not only want but expect to see the bands they missed, to rewrite their own personal musical history so that yes, check, they have seen the seminal rock band the Pixies. Goaded by an endless stream of reissues, they holler and stamp their virtual feet for these bands to return to the stage.
He goes on to liken it to the uptick in vinyl sales over the past bunch of years, citing a "yearning for a second chance to possess something you missed out, nostalgia for something you didn't experience." He's right, and it's scary: the beauty of things is that they can be collected and examined and experienced for what they were, and because they are still exactly that, they can transport you to the time you're nostalgic for. Real living people generally cannot do the same, and that's ok. We should stop asking them to try.