PBR's hipster pedigree.
Who knows how these things happen, but it happened: shitty Pabst Blue Ribbon somehow became the ironic beer of choice for NYC hip-peoples (though, it is waning a bit lately). 'Dude! It's like got a blue ribbon, but it like tastes like crap...Cheers!' As you can see above, even back in the 1940s, PBR was the choice of Bettys and Artists everywhere.
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(also, here's some hipster haikus, some of which mention PBR.)