genetically, they are taller and stronger than Asians. All Germanic people are like that(the Dutch, Norweigians, Danish, Swedish...etc). Many German girls I saw are in perfect S shape. That come from good nutrition and constant exercise.
You are judge them with our Asia-based scale. Have you been to Germany before? just curious.
Most Shanghai / HK girls starve into skinny shape. One old friend, who is in a healthy shape back in US, was anxious at "overwieght" back in HK. It is very amusing to me here.