If you were to open a sole proprietorship ("Einzelunternehmen"), or even just a "Gewerbe" for side-hustles, you can also get things up in a quite lean way and with low overhead costs.
> it erase totally the "I cant do this one shot consulting gig a friend ask me to do"
At leas in Germany, I think the bigger (perceived) hurdle is that most employment contracts state that side-gigs need to be announced to the employer, and just going through those motions is too much of a hurdle.