My folks nearly fainted when they met my husband when we first started dating! He had on running shorts, knee-high socks (one with red stripes, one with blue stipes)and a short-sleeve dress shirt. I was just mortified! I asked him "WHY did you dress like that??" and he said "What? I put on a nice shirt?"!
Over the past 14 years he has slowly evolved from thinking that clothes were merely something to temporarily cover your nakedness to thinking that clothes can actually be nice!