ST. PETERSBURG — Minutes before the Weezer show started at the Mahaffey Theater Friday — house lights up, roadies doing their thing, the crowd of 1,863 finding seats — frontman Rivers Cuomo wandered around the front of the stage, fidgeting, kicking a soccer ball.No one in the audience noticed him. No one hooted or hollered or flashed an oh-my-gosh iPhone. In a white button-down shirt, regimental tie and windbreaker, the 42-year-old looked like an insurance salesman, and he was treated as such.But when the venue finally went dark, and the nebbishy Cuomo ducked backstage and returned just as quickly wearing the same outfit — except this time with a flashy guitar — his fans flipped, the accidental rock star finally getting adulation.Bless the biggest nerds in rockdom, the '90s-born L.A. band still playing the part of losers trying to hang with the hipsters, the hangdog kings of getting sand kicked in their faces.For 90 power-popping minutes, each sing-along chorus was hookier than the next, the guitars loud and crunching yet always in service of the candy-coated mayhem. The bespectacled Cuomo and his cohorts cooed about wanting the girl (El Scorcho), losing the girl (Keep Fishin') and having absolutely zero clue what to do with the girl on the rare occasion they actually get her (If You're Wondering If I Want You To, I Want You To)."We are Weezer," Cuomo deadpanned at one point. "We have come to entertain you. And our means of doing so is to play rock music."They then kicked into the '50s-flecked alt-rock of Surf Wax America, the first time the giant "W" hanging behind them was illuminated in satirical rock posturing. Weezer wants so bad to be Kiss, but the leather pants would probably just give them a rash.Their repeated attempts at thwarting authority — for instance, the novelty chants of We Are All on Drugs or Hash Pipe — were echoed back by a crowd very much in on the joke. A few of their Florida shows have been dedicated to select albums (including 1996's Pinkerton), but this hits set offered a full spectrum of their dysfunction.Cuomo plays the schlub well, but that doesn't stop him from trying to look like a tough guy. He took full advantage of the opera-style seating at the Mahaffey, climbing into the upper deck (after seemingly getting lost in the bowels of the house), awkwardly high-fiving people and taking the odd moment to uncork one of his squirmy solos.Cuomo's vocals and guitars were a little low in the mix at first, but by the end of show, the typically regal theater was filled with smoke and fists and loudness, a darn good impression of a rock joint. The band played their first big hit, Buddy Holly, a song that made them rich. And yet their next cut, the equally overplayed but awesome Beverly Hills, was a lament about how they could never fit in among the pretty people of Hollywood.And therein lies the beautiful, and universal, truth about Weezer. Cuomo can afford to live in a big fat mansion next to Britney Spears. But what's the point if he's too unnerved to ever leave the house and talk to her?Sean Daly can be reached at [email protected] Follow @seandalypoplife on Twitter.