My first reaction when I saw the photo above was to believe that it could be fake, but several searches for more information led to the same answer: It's from a summer performance of a band called Immortal and it's real. The band had used a fake wall of amps for some reason - probably to appear more "hardcore" or whatever it is metal bands aspire to be - and got caught.
The next thought was that perhaps it could it be just a rare one-time act of concert stage trickery. But unfortunately, a series of emails and instant messages to musicians, stage hands, equipment providers and club managers revealed the sad truth: It's not uncommon for bands to set up fake stacks of speakers or amps - hell, empty amp cabinets are frequently sold for that precise purpose.
Was I the last person on the planet to discover this sham? I feel deceived, but I suppose that's what I get for browsing Reddit when I should be writing a Gizmodo post.