That's basically one of the approaches they discuss:

> The legal status for a robot can’t derive from the Legal Entity model, since it implies the existence of human persons behind the legal person to represent and direct it. And this is not the case for a robot.

They also cover treating the robot as a trust fund:

> c. The legal status for a robot can’t derive from the Anglo-Saxon Trust model also called Fiducie or Treuhand in Germany. Indeed, this regime is extremely complex, requires very specialized competences and would not solve the liability issue. More importantly , it would still imply the existence of a human being as a last resort – the trustee or fiduciary – responsible for managing the robot granted with a Trust or a Fiducie.

Edit: The silly thing is that they want to ensure that robots have "the status of electronic persons responsible for making good any damage they may cause" while simultaneously holding that a robot can't be a Natural Person "since the robot would then hold human rights, such as [...] the right to remuneration".

So in their book a robot can't earn money but is personally financially liable for any damage it causes.