Most Berlin sidewalks are uneven cobblestone, not a flat uniform concrete, so the cleaning is probably a lot more difficult than you're envisioning :)

The neighbors snow response contractor had an electric brush on a broom handle, that looked pretty nifty and took like 15 minutes for the whole front to be spotless clean. Then they added a bit of grit, done. The contractor for our block didn’t even show up. Not sure allowing salt would have changed anything.