Probably because those are mapped in OpenStreetMap as service roads (which includes alleys, driveways, parking lanes, etc.). The author of this map seems to hav

Probably because those are mapped in OpenStreetMap as service roads (which includes alleys, driveways, parking lanes, etc.). The author of this map seems to have queried all roads in Berlin from Autobahn down to residential streets, and left out service roads, and bicycle and foot paths.