I guess horizontal stripes would naturally look good on Bret since he's so slim. It makes him look a bit broader. There was something else I also noticed. (And I'd have to go back and look at it) But, in the Sally is Back episode when Jemaine is moving into the new apartment, Bret is wearing a coat with a furry hood. There is also an interview somewhere of him in Wellington, they are leaning up against a desk, and he's wearing a coat with a furry hood. So, I'm guessing that's actually his coat.