Via Page Six: “Jake Gyllenhaal is way beyond the simple choice of boxers vs. briefs. A shopper in Bloomingdale’s underwear department recently watched the Brokeback Mountain star with a salesman ‘combing through every style…A good 10 minutes later, Jake was still at it…holding up a pair of tight white briefs that he’d pulled out of the package to examine, as if he’d never seen tighty whities before in his entire life. It was hilarious. He looked very confused and had a furrowed brow…He was examining undies like an anthropologist in the city’s most highly trafficked department store.'”
Or maybe he’s just used to going commando.