Does anyone know how to avoid gun use for good?
I haven't found a guide yet, that would describe all situations.
(edit: and most obviously I could not figure it out myself either).

Don't shoot the drone - use a glass

Use the right conversations with the shawarma guy, you can get a password and then can give it to the swan when needed rather than shooting.

The robot in the sewers can bribe with the car keys and negotiate with him to go get fixed by Klump

Thanks a lot. Haven't touched the game for a while, but I just might do that today :)

nvm ... after that some dialog appeared that wasn't available earlier and does not seem to be connected to the keys in any way. But it worked.