The line between engaging quirk and inane gimmick is often a thin one. With the release and tour in support of “Reflektor,” Arcade Fire has certainly walked that line, its place on either side determined by one’s appreciation for graffiti campaigns, secret shows and various forms of planned frivolity. On Sunday night, the band brought its shtick to Verizon Center, complete with hipster prom costumes, bobblehead masks and scripted antics that could not distract from an often anemic performance.

An early source of controversy on the tour was the band’s “super not mandatory” policy that concertgoers “wear formal attire or costume” to their shows. A decent percentage of the D.C. crowd took the request to heart, however, showing up in everything from evening wear and masquerade masks to rhinestoned luchador gear and penguin costumes.

On stage, the six-member band has doubled in size, adding percussionists and horn players as if loading up Noah’s ark. Unfortunately, its attempt to make enough noise to fill a cavernous arena often led to indistinct walls of sound that buried the emotional immediacy of the band’s early work under layers of artless excess. This is how melodramatic baroque pop becomes progressive rock.

While the songs were easier to make out as the night went on, the confounding stage set-up made it difficult to follow visually, as the band’s instrumentalists scurried around while bored techs prepared the stage for each song. What good are the fun costumes if you can’t see them from the cheap seats?

The bloated band and the bland stage show were only two of the evening’s head-scratchers and half-measures. Taking creative risks requires follow-through, and whether it was the Ziggy Stardust theatricality, the lampooning of political figures or the Afro-Caribbean dance party, the band came up short. Even the carnival-inspired “Here Comes the Night Time” and its accompanying confetti blizzard seemed to go off too soon.

The reason for many of these choices seems to be “because we can.” For Arcade Fire, the market has spoken: “Reflektor” was a No. 1 album — despite its uninspired, classic rock pastiche and “world music” appropriation — and the band is arguably the biggest rock act in the world. But that kind of decision-making is how Fleetwood Mac made “Tusk,” and how prog rock became a punchline.

The Reflektor tour’s most prominent gimmick/quirk has been the band’s cover songs, which have been tailored to each city’s favorite sons and daughters: Prince in Minneapolis, R.E.M. in Atlanta, and so on. Predictably, the band chose Fugazi’s “Waiting Room” for its D.C. show, performing the hard-core classic with an uncharacteristic verve. It was a good reminder that, as unfortunate as prog rock became, at least it led to punk.

Kelly is a freelance writer.