The word “streetwear” might summon a few images in your head — Kanye West and his high-end Yeezy sneakers, stylish Supreme T-shirts and more. But once upon a time, streetwear was less a mainstream fashion statement and more of an expression of smaller, alternative subcultures like skateboarding, punk rock and surfing. That’s the world into which Bobby Kim, a.k.a Bobby Hundreds, launched a T-shirt business that eventually became the Los Angeles streetwear company The Hundreds. He spoke with Kai Ryssdal about how he kept his streetwear brand successful without “selling out” and his new book, “This Is Not a T-Shirt.”