If there’s anything resembling a post-punk/post-modern/post-whatever cultural subtext to be found on this endlessly infectious debut from Glasgow trio The Fratellis, it might just be this: Rock and roll still hasn’t saved the world and likely never will — but that shouldn’t stop you from enjoying it. While undeniably fixated on the fab-mad days of early ‘90s Brit pop, the roots of the Frat’s musical heritage are a bit more tangled, drawing on the same boisterous UK music hall singalong traditions that have informed bands from the Kinks to Blur, yet seasoned with a whip-smart wit and shrewdly tempered by enough punk-ska-new wave-gleaned sensibilities — and on “Vince the Lovable Stoner,” even a little faux country twang — to keep it all interesting. The swaggering single “Chelsea Dagger” and its infectious doot-da-do-doot chorus could serve as a template for much of the album, with the band briskly tossing off highlights like the iPod TV spot soundtrack “Flathead,” the brash opener “Henrietta” and skiffle-rhythmed “Creepin’ Up the Backstairs” like some giddy hook machine.