Wouldn't trade the grime for anything.
I don't know that the backpack has to do with grime, but at least in Hong Kong every local carries a bag, or a back-pack every day to work, or even when going outside :P
Backpacks are awesome! I think she meant something along the lines of....people in Berlin don't really care what they look like when they go out, and they start opting for more comfortable and practical options (like hiking backpacks vs handbags) and they start getting sloppier about the way they dress and everything else they do because nobody really cares. It's kind of true, but I think the unpretentiousness of the city is what makes it a comfortable place for me!Woot for HKers and backpacks! :D